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Sample records for 1-anilino-8-naphthalene sulfonate ans

  1. 1-Anilino-8-Naphthalene Sulfonate (ANS) Is Not a Desirable Probe for Determining the Molten Globule State of Chymopapain

    PubMed Central

    Qadeer, Atiyatul; Rabbani, Gulam; Zaidi, Nida; Ahmad, Ejaz; Khan, Javed M.; Khan, Rizwan H.

    2012-01-01

    The molten globule (MG) state of proteins is widely detected through binding with 1-anilino-8-naphthalene sulphonate (ANS), a fluorescent dye. This strategy is based upon the assumption that when in molten globule state, the exposed hydrophobic clusters of protein are readily bound by the nonpolar anilino-naphthalene moiety of ANS molecules which then produce brilliant fluorescence. In this work, we explored the acid-induced unfolding pathway of chymopapain, a cysteine proteases from Carica papaya, by monitoring the conformational changes over a pH range 1.0–7.4 by circular dichroism, intrinsic fluorescence, ANS binding, acrylamide quenching, isothermal titration calorimetry (ITC) and dynamic light scattering (DLS). The spectroscopic measurements showed that although maximum ANS fluorescence intensity was observed at pH 1.0, however protein exhibited ∼80% loss of secondary structure which does not comply with the characteristics of a typical MG-state. In contrast at pH 1.5, chymopapain retains substantial amount of secondary structure, disrupted side chain interactions, increased hydrodynamic radii and nearly 30-fold increase in ANS fluorescence with respect to the native state, indicating that MG-state exists at pH 1.5 and not at pH 1.0. ITC measurements revealed that ANS molecules bound to chymopapain via hydrophobic interaction were more at pH 1.5 than at pH 1.0. However, a large number of ANS molecules were also involved in electrostatic interaction with protein at pH 1.0 which, together with hydrophobically interacted molecules, may be responsible for maximum ANS fluorescence. We conclude that maximum ANS-fluorescence alone may not be the criteria for determining the MG of chymopapain. Hence a comprehensive structural analysis of the intermediate is essentially required. PMID:23209794

  2. Effect of carbonylcyanide-4-(trifluoromethoxy)phenylhydrazone (FCCP) on the interaction of 1-anilino-8-naphthalene sulfonate (ANS) with phosphatidylcholine liposomes.

    PubMed

    Cutró, Andrea C; Montich, Guillermo G; Roveri, Oscar A

    2014-04-01

    The weak hydrophobic acid carbonylcyanide-4-(trifluoromethoxy)phenylhydrazone (FCCP) is a protonophoric uncoupler of oxidative phosphorylation in mitochondria. It dissipates the electrochemical proton gradient (ΔμH (+)) increasing the mitochondrial oxygen consumption. However, at concentrations higher than 1 μM it exhibits additional effects on mitochondrial energy metabolism, which were tentatively related to modifications of electrical properties of the membrane. Here we describe the effect of FCCP on the binding of 1-anilino-8-naphthalene sulfonate (ANS) to 1, 2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) unilamellar vesicles. FCCP inhibited the binding of ANS to liposomes either in the gel or in the liquid crystalline phase, by increasing the apparent dissociation constant of ANS. Smaller effect on the dissociation constant was observed at high ionic strength, suggesting that the effect of FCCP is through modification of the electrostatic properties of the membrane interface. In addition, FCCP also decreased (approximately 50 %) the quantum yield and increased the intrinsic dissociation constant of membrane-bound ANS, results that suggest that FCCP makes the environment of the ANS binding sites more polar. On those grounds we postulate that the binding of FCCP: i) increases the density of negative charges in the membrane surface; and ii) distorts the phospholipid bilayer, increasing the mobility of the polar headgroups making the ANS binding site more accessible to water.

  3. 1-Anilino-8-naphthalene sulfonate anion-protein binding depends primarily on ion pair formation.

    PubMed Central

    Matulis, D; Lovrien, R

    1998-01-01

    The ANS- (1-anilino-8-naphthalene sulfonate) anion is strongly, dominantly bound to cationic groups of water-soluble proteins and polyamino acids through ion pair formation. This mode of ANS- binding, broad and pH dependent, is expressed by the quite rigorous stoichiometry of ANS- bound with respect to the available summed number of H+ titrated lysine, histidine, and arginine groups. By titration calorimetry, the integral or overall enthalpies of ANS- binding to four proteins, bovine serum albumin, lysozyme, papain, and protease omega, were arithmetic sums of individual ANS(-)-polyamino acid sidechain binding enthalpies (polyhistidine, polyarginine, polylysine), weighted by numbers of such cationic groups of each protein (additivity of binding enthalpies). ANS- binding energetics to both classes of macromolecules, cationic proteins and synthetic cationic polyamino acids, is reinforced by the organic moiety (anilinonaphthalene) of ANS-. In a much narrower range of binding, where ANS- is sometimes assumed to act as a hydrophobic probe, ANS- may become fluorescent. However, the broad overall range is sharply dependent on electrostatic, ion pair formation, where the organic sulfonate group is the major determinant of binding. PMID:9449342

  4. Crystallographically mapped ligand binding differs in high and low IgE binding isoforms of birch pollen allergen bet v 1.

    PubMed

    Kofler, Stefan; Asam, Claudia; Eckhard, Ulrich; Wallner, Michael; Ferreira, Fátima; Brandstetter, Hans

    2012-09-07

    The ability of pathogenesis-related proteins of family 10 to bind a broad spectrum of ligands is considered to play a key role for their physiological and pathological functions. In particular, Bet v 1, an archetypical allergen from birch pollen, is described as a highly promiscuous ligand acceptor. However, the detailed recognition mechanisms, including specificity factors discriminating binding properties of naturally occurring Bet v 1 variants, are poorly understood. Here, we report crystal structures of Bet v 1 variants in complex with an array of ligands at a resolution of up to 1.2 Å. Residue 30 within the hydrophobic pocket not only discriminates in high and low IgE binding Bet v 1 isoforms but also induces a drastic change in the binding mode of the model ligand deoxycholate. Ternary crystal structure complexes of Bet v 1 with several ligands together with the fluorogenic reporter 1-anilino-8-naphthalene sulfonate explain anomalous fluorescence binding curves obtained from 1-anilino-8-naphthalene sulfonate displacement assays. The structures reveal key interaction residues such as Tyr83 and rationalize both the binding specificity and promiscuity of the so-called hydrophobic pocket in Bet v 1. The intermolecular interactions of Bet v 1 reveal an unexpected complexity that will be indispensable to fully understand its roles within the physiological and allergenic context.

  5. Impact of Ciprofloxacin and Chloramphenicol on the Lipid Bilayer of Staphylococcus aureus: Changes in Membrane Potential

    PubMed Central

    Páez, Paulina L.; Becerra, María C.; Albesa, Inés

    2013-01-01

    The present study was undertaken to explore the interaction of ciprofloxacin and chloramphenicol with bacterial membranes in a sensitive and in a resistant strains of Staphylococcus aureus by using 1-anilino-8-naphthalene sulfonate (ANS). The binding of this probe to the cell membrane depends on the surface potential, which modulates the binding constant to the membrane. We observed that these antibiotics interacted with the bilayer, thus affecting the electrostatic surface potential. Alterations caused by antibiotics on the surface of the bacteria were accompanied by a reduction in the number of binding sites and an increase in the ANS dissociation constant in the sensitive strain, whereas in the ciprofloxacin-resistant strain no significant changes were detected. The changes seen in the electrostatic surface potential generated in the membrane of S. aureus by the antibiotics provide new aspects concerning their action on the bacterial cell. PMID:23762834

  6. [Solubilizing effect and inclusion reaction of cyclic bisdesmosides from tubers of Bolbostemma paniculatum].

    PubMed

    Miyakoshi, M; Kasai, R; Nishioka, M; Ochiai, H; Tanaka, O

    1990-12-01

    Tubeimosides I, II and III (cyclic bisdesmosides) have been isolated from Chinese cucurbitaceous crude drug Tu-bei-mu, a tuber of Bolbostemma paniculatum (Maxim.) Franquet. Solubilizing effects of these cyclic bisdesmosides on water insoluble or less-soluble compounds were examined. It was revealed that cyclic bisdesmosides were effective on increasing the solubility of Yellow OB, dl-alpha-tocopherol and saponin A from Sapindus mukurossi. The critical micell concentration (cmc) and association number as well as diameter of micell of tubeimoside I in water were also measured. The interaction of tubeimoside I with 1-anilino-8-naphthalene-sulfonate (ANS) in aqueous solution was investigated photometrically. It was observed that tubeimoside I strongly enhanced the intensity of fluorescence of ANS, suggesting the significant formation of inclusion complex.

  7. Degree of dissociation of apohemoglobin studied by nano-second fluorescence-polarization technique.

    PubMed

    Kinosita, K; Mitaku, S; Ikegami, A

    1975-05-30

    A fluorescent dye 1-anilino-8-naphthalene sulfonate was complexed with human apohemoglobin and sperm whale apomyoglobin. Nanosecond fluorescence-polarization kinetics were measured for each of these complexes in KC1 solutions to obtain their fluorescence lifetimes and rotational correlation times. The rotational correlation time of apohemoglobin-dye complex was found to be 21 ns, which was about twice that of apomyoglobin-dye complex, 11 ns. These values were constant over an ionic strength range from 0 to 1.7. Circular dichroism spectra (215-300 nm) and fluorescence lifetimes of the complexes were also found to be independent of the ionic strength, indicating that no gross conformational change occurs with the change in the salt concentration, These results suggest that apohemoglobin remains dimeric over the ionic-strength range examined.

  8. pH treatment as an effective tool to select the functional and structural properties of yak milk caseins.

    PubMed

    Liu, H N; Zhang, C; Zhang, H; Guo, H Y; Wang, P J; Zhu, Y B; Ren, F Z

    2013-09-01

    Qula is made from yak milk after defatting, acidifying, and drying. Yak milk caseins are purified from Qula by dissolving in alkali solution. The effects of different pH treatments on the functional and structural properties of yak milk caseins were investigated. Over a broad range of pH (from 6.0 to 12.0), functional properties of yak milk caseins, including solubility, emulsifying activities, and thermal characteristics, and the structural properties, including 1-anilino-8-naphthalene-sulfonate fluorescence, turbidity and particle diameter, were evaluated. The results showed that the yak milk casein yield increased as the pH increased from 6.0 to 12.0. The solubility dramatically increased as the pH increased from 6.0 to 8.0, and decreased as the pH increased from 9.0 to 12.0. The changes in emulsifying activity were not significant. Caseins were remarkably heat stable at pH 9.0. The turbidity of the casein solution decreased rapidly as the pH increased from 6.0 to 12.0, and the results suggested that reassembled casein micelles were more compact at low pH than high pH. At pH values higher than 8.0, the yield of yak milk caseins reached more than 80%. The highest solubility was at pH 8.0, the best emulsification was at pH 10.0 and the greatest thermal stability was at pH 9.0. According to the functional characteristics of yak milk caseins, alkali conditions (pH 8.0-10.0) should be selected for optimum production. These results suggested that pH-dependent treatment could be used to modify the properties of yak milk caseins by appropriate selection of the pH level.

  9. Rh-Catalyzed Asymmetric Hydrogenation of α-Substituted Vinyl Sulfones: An Efficient Approach to Chiral Sulfones.

    PubMed

    Shi, Liyang; Wei, Biao; Yin, Xuguang; Xue, Peng; Lv, Hui; Zhang, Xumu

    2017-03-03

    Rh/(S)-(+)-DTBM-Segphos complex catalyzed asymmetric hydrogenation of α-substituted vinyl sulfones has been achieved, furnishing the desired products in high yields and excellent enantioselectivities (>90% yield, up to 99% ee). This method provided an efficient approach to α-substituted chiral sulfones under mild conditions and has potential applications in organic synthesis.

  10. Pyrolysis Pathways of Sulfonated Polyethylene, an Alternative Carbon Fiber Precursor

    SciTech Connect

    Younker, Jarod M; Saito, Tomonori; Hunt, Marcus A; Beste, Ariana; Naskar, Amit K

    2013-01-01

    Sulfonated polyethylene is an emerging precursor for the production of carbon fibers. Pyrolysis of sulfonated polyethylene was characterized by thermogravimetric analysis (TGA). n-heptane-4-sulfonic acid (H4S) was selected as a model compound for the study of sulfonated polyethylene. Density functional theory and conventional transition state theory were used to determine the rate constants of pyrolysis for H4S from 300-1000 K. Multiple reaction channels from two different mechanisms were explored: 1) internal five-centered elimination (Ei 5) and 2) radical chain reaction. The pyrolysis of H4S was simulated with kinetic Monte Carlo (kMC) to obtain TGA plots that compared favorably to experiment. We observed that at tem- peratures < 550 K, the radical mechanism was dominant and yielded the trans-alkene, whereas cis-alkene was formed at higher temperatures from the internal elimination. The maximum rates of % mass loss became independent of initial OH radical concentration at 440-480 K. Experimentally, the maximum % mass loss occurred from 440-460 K (heating rate dependent). Activation energies derived from the kMC-simulated TGAs of H4S (26-29 kcal/mol) agreed with experiment for sulfonated polyethylene ( 31 kcal/mol). The simulations revealed that in this region, decomposition of radical HOSO2 became competitive to H abstraction by HOSO2, making OH the carrying radical for the reaction chain. The maximum rate of % mass loss for internal elimination was observed at temperatures > 600 K. Low-scale carbonization utilizes temperatures < 620 K; thus, internal elimination will not be competitive. Ei5 elimination has been studied for sulfoxides and sulfones, but this represents the first study of internal elimination in sulfonic acids. Nonlinear Arrhenius plots were found for all bimolecular reactions. The most significant nonlinear behavior was observed for reactions where the barrier was small. For reactions with low activation barriers, nonlinearity was traced to

  11. 40 CFR 721.950 - Sodium salt of an alkylated, sulfonated aromatic (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., sulfonated aromatic (generic name). 721.950 Section 721.950 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.950 Sodium salt of an alkylated, sulfonated... chemical substance identified generically as a sodium salt of an alkylated, sulfonated aromatic (PMN...

  12. 40 CFR 721.950 - Sodium salt of an alkylated, sulfonated aromatic (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., sulfonated aromatic (generic name). 721.950 Section 721.950 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.950 Sodium salt of an alkylated, sulfonated... chemical substance identified generically as a sodium salt of an alkylated, sulfonated aromatic (PMN...

  13. Sulfonation, an underexploited area: from skeletal development to infectious diseases and cancer

    PubMed Central

    Leung, Ada W.Y.; Backstrom, Ian; Bally, Marcel B.

    2016-01-01

    Sulfonation is one of the most abundant cellular reactions modifying a wide range of xenobiotics as well as endogenous molecules which regulate important biological processes including blood clotting, formation of connective tissues, and functionality of secreted proteins, hormones, and signaling molecules. Sulfonation is ubiquitous in all tissues and widespread in nature (plants, animals, and microorganisms). Although sulfoconjugates were discovered over a century ago when, in 1875, Baumann isolated phenyl sulfate in the urine of a patient given phenol as an antiseptic, the significance of sulfonation and its roles in human diseases have been underappreciated until recent years. Here, we provide a current overview of the significance of sulfonation reactions in a variety of biological functions and medical conditions (with emphasis on cancer). We also discuss research areas that warrant further attention if we are to fully understand how deficiencies in sulfonation could impact human health which, in turn, could help define treatments to effect improvements in health. PMID:27322429

  14. Synthesis, micellisation and interaction of novel quaternary ammonium compounds derived from l-Phenylalanine with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine as model membrane in relation to their antibacterial activity, and their selectivity over human red blood cells.

    PubMed

    Joondan, Nausheen; Caumul, Prakashanand; Akerman, Matthew; Jhaumeer-Laulloo, Sabina

    2015-02-01

    A series of quaternary ammonium compounds (QUATS) derived from l-Phenylalanine have been synthesized and their antibacterial efficiencies were determined against various strains of Gram-positive and Gram-negative bacteria. The antibacterial activity increased with increasing chain length, exhibiting a cut-off effect at C14 for Gram-positive and C12 for Gram-negative bacteria. The l-Phenylalanine QUATS displayed enhanced antibacterial properties with a higher cut-off point compared to their corresponding l-Phenylalanine ester hydrochlorides. The CMC was correlated with the MIC, inferring that micellar activity contributes to the cut-off effect in antibacterial activity. The hemolytic activities (HC50) of the QUATS against human red blood cells were also determined to illustrate the selectivity of these QUATS for bacterial over mammalian cells. In general, the MIC was lower than the HC50, and assessment of the micellar contribution to the antibacterial and hemolytic evaluation in TBS as a common medium confirmed that these QUATS can act as antibacterial, yet non-toxic molecules at their monomer concentrations. The interaction of the QUATS with the phospholipid vesicles (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC) in the presence of 1-anilino-8-naphthalene sulfonate (ANS) and 1,6-diphenyl-1,3,5-hexatriene (DPH) as fluorescence probes showed that the presence of the quaternary ammonium moiety causes an increase in hydrophobic interactions, thus causing an increase in antibacterial activity.

  15. Inhibitory effect of copper nanoparticles on rosin modified surfactant induced aggregation of lysozyme.

    PubMed

    Ishtikhar, Mohd; Usmani, Salman Sadullah; Gull, Nuzhat; Badr, Gamal; Mahmoud, Mohamed H; Khan, Rizwan Hasan

    2015-01-01

    Protein aggregation is associated with many serious diseases including Parkinson's and Alzheimer's. Protein aggregation is a primary problem related with the health of industrial workers who work with the surfactants, metal ions, and cosolvents. We have synthesized rosin-based surfactants, i.e., quaternary amines of rosin diethylaminoethyl esters (QRMAE), which is an ester of rosin acid with polyethylene glycol monomethyl ether. Here, we report the thermal aggregation of lysozyme induced by QRMAE at 65 °C and pH 7.4 for a given time period in which amorphous aggregates are formed and confirm that copper-nanoparticles have the ability to inhibit QRMAE-induced aggregation compared with zinc and silver-nanoparticles. Aggregation experiments was evaluated using several spectroscopic methods and dye binding assay, such as turbidity, Rayleigh light scattering, 1-anilino-8-naphthalene sulfonate (ANS), Thioflavin T (Th T), congo red (CR) and circular dichroism (CD), that was further supported by scanning electron microscopy (SEM) and SEM with EDX. The therapeutic use of nanoparticles and the fact that rosin possesses excellent film-forming properties, and that its derivatives have pharmaceuticals application such as micro encapsulation, coating and film forming, it's matrix materials are used for sustained and controlled release tablets, renders importance and application to the present study.

  16. A single mutation induces molten globule formation and a drastic destabilization of wild-type cytochrome c at pH 6.0.

    PubMed

    Alam Khan, Md Khurshid; Das, Utpal; Rahaman, Md Hamidur; Hassan, Md Imtaiyaz; Srinivasan, A; Singh, Tej P; Ahmad, Faizan

    2009-06-01

    Amino acid sequences of seven subfamilies of cytochromes c show that other than heme binding residues there are only four positions which are conserved in all subfamilies: Gly/Ala6, Phe/Tyr10, Leu/Val/Phe94, and Tyr/Trp/Phe97. These residues are 90% conserved in all sequences reported and are also considered to be involved in a common folding nucleus. To determine the importance of conserved interactions offered by the side chain of Leu94, we made an L94G mutant of horse cytochrome c. Characterization of this mutant by the far-UV, near-UV, and Soret circular dichroism, intrinsic and 1-Anilino-8-naphthalene sulfonate fluorescence, and dynamic light scattering measurements led to the conclusion that the L94G mutant has all the common structural characteristics of a molten globule at pH 6.0 and 25 degrees C. NaCl induces a cooperative transition between the acid-denatured state and a state of L94G having all the common structural characteristics of a pre-molten-globule state at pH 2 and 25 degrees C. Thermal denaturation studies showed that the midpoint of denaturation of the mutant is 28 degrees C less than that of the wild-type protein. Interestingly, the structure analysis using the coordinates given in the Protein Data Bank (1hrc) also suggested that the L94G mutant would be less stable than the wild-type protein.

  17. Urea Unfolding Study of E. coli Alanyl-tRNA Synthetase and Its Monomeric Variants Proves the Role of C-Terminal Domain in Stability

    PubMed Central

    Banerjee, Baisakhi; Banerjee, Rajat

    2015-01-01

    E. coli alanyl-tRNA exists as a dimer in its native form and the C-terminal coiled-coil part plays an important role in the dimerization process. The truncated N-terminal containing the first 700 amino acids (1–700) forms a monomeric variant possessing similar aminoacylation activity like wild type. A point mutation in the C-terminal domain (G674D) also produces a monomeric variant with a fivefold reduced aminoacylation activity compared to the wild type enzyme. Urea induced denaturation of these monomeric mutants along with another alaRS variant (N461 alaRS) was studied together with the full-length enzyme using various spectroscopic techniques such as intrinsic tryptophan fluorescence, 1-anilino-8-naphthalene-sulfonic acid binding, near- and far-UV circular dichroism, and analytical ultracentrifugation. Aminoacylation activity assay after refolding from denatured state revealed that the monomeric mutants studied here were unable to regain their activity, whereas the dimeric full-length alaRS gets back similar activity as the native enzyme. This study indicates that dimerization is one of the key regulatory factors that is important in the proper folding and stability of E. coli alaRS. PMID:26617997

  18. Spectroscopic analyses of manganese ions effects on the conformational changes of inorganic pyrophosphatase from psychrophilic Shewanella sp. AS-11.

    PubMed

    Ginting, Elvy Like; Maeganeku, Chihiro; Motoshima, Hiroyuki; Watanabe, Keiichi

    2014-02-01

    Mn²⁺ ions influence the activity, temperature dependence, and thermostability of the psychrophilic Shewanella-PPase (Sh-PPase), and are required to function in cold environments. The functional characteristics of Sh-PPase on activation with Mn²⁺ ions are possibly related to conformational changes in the molecule. In this study, conformational changes of Sh-PPase on activation with Mn²⁺ ions were analyzed in solution by fluorescence spectroscopy analysis of intrinsic tryptophan residues, 1-anilino-8-naphthalene sulfonate fluorescence, and circular dichroism spectroscopy. For Sh-PPase, Mn²⁺ ions did not affect the flexibility of the tryptophan residues and secondary structure of the enzyme. However, the microenvironment of the tryptophan residues and surface area of Sh-PPase were more hydrophilic on activation with Mn²⁺ ions. These results indicate that activation with Mn²⁺ ions causes conformational changes around the aromatic amino acid residues and affects the hydrophobicity of the enzyme surface, which results in conformational changes. Substrate-induced conformational changes reflect that metal-free Sh-PPase in solution indicated an open structure and will be a close structure when binding substrate. In combination of our spectroscopic analyses on Sh-PPase, it can be concluded that activation with Mn²⁺ ions changes some conformation of Sh-PPase molecule in solution.

  19. Hydrodynamics of horseradish peroxidase revealed by global analysis of multiple fluorescence probes.

    PubMed Central

    Brunet, J E; Vargas, V; Gratton, E; Jameson, D M

    1994-01-01

    Previous fluorescence studies of horseradish peroxidase conjugated with protoporphyrin IX suggested that the protein behaved hydrodynamically as a prolate ellipsoid of axial ratio 3 to 1. The present study, designed to further investigate the hydrodynamics of this protein, exploits a series of probes, noncovalently bound to the heme binding site of apo-horseradish peroxidase, having different orientations of the excitation and emission transition dipoles with respect to the protein's rotational axes. The probes utilized included protoporphyrin IX and the naphthalene probes 1-anilino-8-naphthalene sulfonate, 2-p-toluidinyl-6-naphthalene sulfonate, and 4,4'-bis(1-anilino-8-naphthalene sulfonate). Time-resolved data were obtained using multifrequency phase fluorometry. The global analysis approach to the determination of molecular shape using multiple probes was evaluated by utilizing all data sets while maintaining a constant molecular shape for the protein. The results indicated that, in such analyses, probes exhibiting a single exponential decay and limited local motion have the major weight in the evaluation of the axial ratio. Probes that show complex decay patterns and local motions, such as the naphthalene derivatives, give rise to significant uncertainties in such global treatments. By explicitly accounting for the effect of such local motion, however, the shape of the protein can be reliably recovered. PMID:8161698

  20. Coupling hydrogen separation with butanone hydrogenation in an electrochemical hydrogen pump with sulfonated poly (phthalazinone ether sulfone ketone) membrane

    NASA Astrophysics Data System (ADS)

    Huang, Shiqi; Wang, Tao; Wu, Xuemei; Xiao, Wu; Yu, Miao; Chen, Wei; Zhang, Fengxiang; He, Gaohong

    2016-09-01

    This work reports the novel work of coupling H2/CO2 separation with biomass-derived butanone hydrogenation in non-fluorinated sulfonated poly (phthalazinone ether sulfone ketone) (SPPESK) electrochemical hydrogen pump (EHP) reactor. Due to higher resistance to swelling, SPPESK-based EHP reactor exhibits more excellent reaction rate in elevated temperature (60 °C) and higher butanone concentration (2 M) as 270, 260 nmol cm-2 s-1, respectively, higher than 240, 200 nmol cm-2 s-1of Nafion-based EHP reactors. Also, the SPPESK-based EHP reactor remains 90% of initial hydrogenation rate after 4 batches, better than that of Nafion-based EHP reactors, which is only 62%. The energy efficiency of EHP separator reaches 40% under H2/CO2 mixture feed mode, and electricity of about 0.3 kWh is consumed per Nm3 H2 product, being superior to energy consumption compared with alternative processes like PSA and electrolysis of water. In addition, SPPESK-based EHP exhibits better hydrogenation stability due to lower CO2 permeation than Nafion. With increasing CO2 content in H2 feed, hydrogenation rate almost keeps constant at around 210 nmol cm-2 s-1 in SPPESK-based EHP reactor while decreases fast to 50 nmol cm-2 s-1 in Nafion/PTFE-based EHP reactor. These results show integration of gas separation with hydrogenation reactor is feasible in SPPESK-based EHP reactor.

  1. An analysis of the kinetics of oxidation of ascorbate at poly(aniline)-poly(styrene sulfonate) modified microelectrodes.

    PubMed

    Bonastre, A M; Sosna, M; Bartlett, P N

    2011-03-28

    A detailed kinetic study is provided for the oxidation of ascorbate at poly(aniline)-poly(styrene sulfonate) coated microelectrodes. Flat films with a low degree of polymer spillover and a thickness much lower than the microelectrode radius were produced by controlled potentiodynamic electrodeposition. The currents for ascorbate oxidation are found to be independent of the polymer thickness, indicating that the reaction occurs at the outer surface of the polymer film. At low ascorbate concentrations, below around 40 mM, the currents are found to be mass transport limited. At higher ascorbate concentrations the currents became kinetically limited. The experimental data for measurements at a range of potentials are fitted to a consistent kinetic model and the results summarized in a case diagram. The results obtained for the poly(aniline)-(polystyrene sulfonate) coated microelectrode are compared to those for a poly(aniline)-poly(vinyl sulfonate) coated microelectrode and to the results of an earlier study of the reaction at poly(aniline)-poly(vinyl sulfonate) coated rotating disc electrodes. For poly(aniline)-poly(styrene sulfonate) the oxidation of ascorbate is found to proceed by one electron reaction whereas for poly(aniline)-poly(vinyl sulfonate) the reaction is found to be a two electron oxidation.

  2. 21 CFR 573.600 - Lignin sulfonates.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Lignin sulfonates. 573.600 Section 573.600 Food... Additive Listing § 573.600 Lignin sulfonates. Lignin sulfonates may be safely used in animal feeds in... feeds, as liquid lignin sulfonate, in an amount not to exceed 11 percent of the molasses. (4) As...

  3. 21 CFR 573.600 - Lignin sulfonates.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Lignin sulfonates. 573.600 Section 573.600 Food... Additive Listing § 573.600 Lignin sulfonates. Lignin sulfonates may be safely used in animal feeds in... feeds, as liquid lignin sulfonate, in an amount not to exceed 11 percent of the molasses. (4) As...

  4. The role of proline in the prevention of aggregation during protein folding in vitro.

    PubMed

    Kumar, T K; Samuel, D; Jayaraman, G; Srimathi, T; Yu, C

    1998-10-01

    Proline effectively inhibits protein aggregation during the refolding of bovine carbonic anhydrase. Other osmolytes used such as glycine and ethylene glycol fail to exhibit the 'aggregation-blockade' role shown by proline. Results of viscosity and ANS fluorescence (1-anilino-8-naphthalene sulphonic acid) experiments suggest that proline at high concentrations forms an ordered supramolecular assembly. Based on these results, it is proposed that proline behaves as a protein folding chaperone due to the formation of an ordered, amphipathic supramolecular assembly. To our knowledge, this is the first report wherein proline is proposed as a protein folding aid.

  5. Development and validation of an automated static headspace gas chromatography-mass spectrometry (SHS-GC-MS) method for monitoring the formation of ethyl methane sulfonate from ethanol and methane sulfonic acid.

    PubMed

    Jacq, Karine; Delaney, Ed; Teasdale, Andrew; Eyley, Steve; Taylor-Worth, Karen; Lipczynski, Andrew; Reif, Van D; Elder, David P; Facchine, Kevin L; Golec, Simon; Oestrich, Rolf Schulte; Sandra, Pat; David, Frank

    2008-12-15

    An automated sample preparation and analysis procedure was developed to monitor the formation of ethyl methane sulfonate from reaction mixtures containing ethanol and methane sulfonic acid. The system is based on a liquid handling robot combined with a static headspace module. The formed ethyl methane sulfonate is analysed after derivatisation with pentafluorothiophenol using static headspace-gas chromatography-mass spectrometry (SHS-GC-MS). Using the automated reaction-derivatisation-headspace GC-MS system, the formation of ethyl methane sulfonate can be monitored in different reaction mixtures under different reaction conditions, including temperature, water content and pH. Excellent linearity, repeatability and robustness were obtained, allowing the system to be used in kinetic studies.

  6. Mapping protein cysteine sulfonic acid modifications with specific enrichment and mass spectrometry: an integrated approach to explore the cysteine oxidation.

    PubMed

    Chang, Yuan-Chang; Huang, Chien-Ning; Lin, Chia-Hung; Chang, Huan-Cheng; Wu, Chih-Che

    2010-08-01

    Oxidation of thiol proteins, which results in conversion of cysteine residues to cysteine sulfenic, sulfinic or sulfonic acids, is an important posttranslational control of protein function in cells. To facilitate the analysis of this process with MALDI-MS, we have developed a method for selective enrichment and identification of peptides containing cysteine sulfonic acid (sulfopeptides) in tryptic digests of proteins based on ionic affinity capture using polyarginine-coated nanodiamonds as high-affinity probes. The method was applied to selectively concentrate sulfopeptides from either a highly dilute solution or a complex peptide mixture in which the abundance of the sulfonated analyte is as low as 0.02%. The polyarginine-coated probes exhibit a higher affinity for peptides containing multiple sulfonic acids than peptides containing single sulfonic acid. The limit of the detection is in the femtomole range, with the MALDI-TOF mass spectrometer operating in the negative ion mode. The results show that the new approach has good specificity even in the presence of phosphopeptides. An application of this method for selective enrichment and structural identification of sulfopeptides is demonstrated with the tryptic digests of performic-acid-oxidized BSA.

  7. Predicting the Solution Morphology of a Sulfonated Pentablock Copolymer in an Arbitrary Solvent Mixture

    NASA Astrophysics Data System (ADS)

    Ford, Jamie; Kyei-Manu, William; Winey, Karen

    2013-03-01

    Block copolymers self assemble into a wide array of morphologies in solvents. To predict the solution morphology of the polymer, we assess the interactions between the individual blocks and the solvent or solvents. Here, we use the Hansen solubility parameters to calculate the interactions between a library of solvents and an ABCBA pentablock copolymer with non-polar A and B blocks and a polar, sulfonated C block to predict the expected morphology for a given solvent and compare it to our small-angle X-ray scattering data. In non-polar solvents, we observe micelles with a C core and an A-B corona. We observe inverted micelles in polar solvents - an A-B core with a C corona. We extended our methodology to mixed polar/non-polar solvent systems to predict the solvent ratios corresponding to the transition from micelles to inverted micelles.

  8. Aldicarb sulfone

    Integrated Risk Information System (IRIS)

    Aldicarb sulfone ; CASRN 1646 - 88 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  9. Preparation of a sulfonated carbonaceous material from lignosulfonate and its usefulness as an esterification catalyst.

    PubMed

    Lee, Duckhee

    2013-07-10

    Sulfonated carbonaceous material useful as a solid acid catalyst was prepared from lignosulfonate, a waste of the paper-making industry sulfite pulping process, and characterized by 13C-NMR, FT-IR, TGA, SEM and elemental analysis, etc. The sulfonic acid group density and total density of all acid groups in the sulfonated carbonaceous material was determined by titration to be 1.24 mmol/g and 5.90 mmol/g, respectively. Its catalytic activity in the esterification of cyclohexanecarboxylic acid with anhydrous ethanol was shown to be comparable to that of the ionic exchange resin Amberlyst-15, when they were used in the same amount. In the meantime, the sulfonic acid group was found to be leached out by 26%-29% after it was exposed to hot water (95 °C) for 5 h. The catalytic usefulness of the prepared carbonaceous material was investigated by performing esterifications.

  10. Hexafluoroisopropanol-induced helix-sheet transition of stem bromelain: correlation to function.

    PubMed

    Dave, Sandeep; Dkhar, H Kitdorlang; Singh, Manvendra Pratap; Gupta, Garima; Chandra, Vemika; Mahajan, Sahil; Gupta, Pawan

    2010-06-01

    Stem bromelain is a proteolytic phytoprotein with a variety of therapeutic effects. Understanding its structural properties could provide insight into the mechanisms underlying its clinical utility. Stem bromelain was evaluated for its conformational and folding properties at the pH conditions it encounters when administered orally. It exists as a partially folded intermediate at pH 2.0. The conformational changes to this intermediate state were evaluated using fluorinated alcohols known to induce changes similar to those seen in vivo. Studies using circular dichroism, fluorescence emission spectroscopy, binding of the hydrophobic dye 1-anilino-8-naphthalene sulfonic acid and mass spectrometry indicate that treatment with 10-30% hexafluoroisopropanol induces the partially folded intermediate to adopt much of the native protein's secondary structure, but only a rudimentary tertiary structure, characteristic of the molten globule state. Addition of slightly higher concentrations of hexafluoroisopropanol caused transformation from an alpha-helix to a beta-sheet and induced formation of a compact nonnative structure. This nonnative form was more inhibitory of cell survival than either the native or the partially folded intermediate forms, as measured by enhanced suppression of proliferative cues (e.g., extracellular-signal-regulated kinase) and initiation of apoptotic events. The nonnative form also showed better antitumorigenic properties, as evaluated using an induced two-stage mouse skin papilloma model. In contrast, the nonnative state showed only a fraction of the proteolytic activity of the native form. This study demonstrates that hexafluoroisopropanol can induce a conformational change in stem bromelain to a form with potentially useful therapeutic properties different from those of the native protein.

  11. Trifluoroethanol stabilizes the molten globule state and induces non-amyloidic turbidity in stem bromelain near its isoelectric point.

    PubMed

    Dave, Sandeep; Mahajan, Sahil; Chandra, Vemika; Gupta, Pawan

    2011-11-01

    Stem bromelain (SBM) is a therapeutic protein that has been studied for alkaline denaturation in the intestines, the principal site of its absorption. In this study, we investigated fluorinated alcohol 2,2,2-trifluoroethanol (TFE)-induced conformational changes in the specific/pre-molten globule (SMG) state of SBM observed at pH 10 by spectroscopic methods. Far-UV circular dichroism (CD) spectra showed that the protein retained its native-like secondary structure at TFE concentrations of up to 30% with a pronounced minimum at 222 nm, characteristic of a helix. However, addition of slightly higher TFE concentrations (≥40%) resulted in an ∼2.5-fold induction of this helical feature and a time-dependent increase in non-amyloidic turbidity as evidenced by turbidometric, Congo red-binding, and Thioflavin T (ThT)-binding studies. Near-UV CD spectra suggested a gradual but significant loss of tertiary structure at 10-30% TFE. Tryptophan studies showed blue-shifted fluorescence, although the number of accessible tryptophans remained the same up to 30% TFE. The SMG showed enhanced binding of the fluorescent probe 1-anilino-8-naphthalene sulfonic acid (ANS) up to 30% TFE, beyond which binding plateaued. Thermal and guanidine hydrochloride (GdnHCl) transition studies in the near-UV range indicated a single cooperative transition for the SMG state in the presence of 30% TFE, similar to that observed for native SBM at pH 7.0 (although with different T(m)s), unlike the SMG state. TFE (30%) appeared to induce native-like stability to the original SMG. These observations suggest a transformation of the SMG to a characteristic molten globule (MG) conformation at 30% TFE, possibly due to TFE-induced rearrangement of hydrophobic interactions at the protein's isoelectric point.

  12. Induction of 'molten globule' like state in acid-denatured state of unmodified preparation of stem bromelain: implications of disulfides in protein folding.

    PubMed

    Gupta, Pawan; Khan, Rizwan H; Saleemuddin, M

    2003-12-01

    A denatured state of unmodified preparation of stem bromelain representing a structureless form has been characterized at pH 2.0 and the effect of increasing concentration of TFE on the acid-denatured state has been investigated by circular dichroism (CD), fluorescence emission spectroscopy and binding of the hydrophobic dye, 1-anilino-8-naphthalene sulfonic acid (ANS). Far-UV CD spectra show considerable accumulation of secondary structure when the acid-denatured bromelain is subjected to 70% (v/v) TFE and exhibited close resemblance to spectral features of those of pH 7.0 preparation. Interestingly, the acid-denatured state also regained some tertiary structure/interactions, with increasing concentration of TFE and at 60% (v/v) TFE, these approached almost those of the native like state. However, further increase to 70% (v/v) TFE resulted in complete loss of tertiary structure/interactions. Tryptophan fluorescence emission studies also suggested the induction of significant compact structure at 60% (v/v) concentration of TFE. In addition the acid-denatured state showed enhanced binding of ANS in presence of 60% (v/v) TFE. Taken together these observations suggest the existence of a molten globule state in acid-denatured bromelain between 60 and 70% (v/v) TFE. A similar molten globule state under identical conditions has been identified in reduced and carboxymethylated preparation of stem bromelain as reported in our earlier communication [Arch. Biochem. Biophys. 413 (2003) 199]. Comparison suggests unfolding/folding behavior of the bromelain to be independent of the intactness of the disulfide bonds.

  13. Folding and aggregation of TEM beta-lactamase: analogies with the formation of inclusion bodies in Escherichia coli.

    PubMed Central

    Georgiou, G.; Valax, P.; Ostermeier, M.; Horowitz, P. M.

    1994-01-01

    The enzyme TEM beta-lactamase has been used as a model for understanding the pathway leading to formation of inclusion bodies in Escherichia coli. The equilibrium denaturation of TEM beta-lactamase revealed that an intermediate that has lost enzymatic activity, native protein fluorescence, and UV absorption, but retains 60% of the native circular dichroism signal, becomes populated at intermediate (1.0-1.4 M) concentrations of guanidium chloride (GdmCl). This species exhibits a large increase in bis-1-anilino-8-naphthalene sulfonic acid fluorescence, indicating the presence of exposed hydrophobic surfaces. When TEM beta-lactamase was unfolded in different initial concentrations of GdmCl and refolded to the same final conditions by dialysis a distinct minimum in the yield of active protein was observed for initial concentrations of GdmCl in the 1.0-1.5 M range. It was shown that the lower reactivation yield was solely due to the formation of noncovalently linked aggregates. We propose that the aggregation of TEM beta-lactamase involves the association of a compact state having partially exposed hydrophobic surfaces. This hypothesis is consistent with our recent findings that TEM beta-lactamase inclusion bodies contains extensive secondary structure (Przybycien TM, Dunn JP, Valax P, Georgiou G, 1994, Protein Eng 7:131-136). Finally, we have also shown that protein aggregation was enhanced at higher temperatures and in the presence of 5 mM dithiothreitol and was inhibited by the addition of sucrose. These conditions exert a similar effect on the formation of inclusion bodies in vivo. PMID:7703842

  14. Fate of perfluorinated carboxylates and sulfonates during snowmelt within an urban watershed.

    PubMed

    Meyer, Torsten; De Silva, Amila O; Spencer, Christine; Wania, Frank

    2011-10-01

    The transport dynamics of perfluorinated carboxylic acids and sulfonates during snowmelt in the highly urbanized Highland Creek watershed in Toronto, Canada was investigated by analyzing river water, bulk snow, and groundwater, sampled in February and March 2010, by means of liquid chromatography-tandem mass spectrometry. Perfluorohexanoate, perfluorooctanoate, and perfluorooctane sulfonate were dominant in river water, with concentrations of 4.0-14 ng·L(-1), 2.2-7.9 ng·L(-1), and 2.1-6.5 ng·L(-1), respectively. Relatively high levels of perfluorohexanoate may be related to the recent partial replacement in various consumer products of perfluorooctyl substances with shorter-chained perfluorinated compounds (PFCs). Highest PFC concentrations were found within the more urbanized part of the drainage area, suggestive of residential, industrial, and/or traffic-related sources. The riverine flux of PFCs increased during the snowmelt period, but only approximately one-fifth of the increased flux can be attributed to PFCs present in the snowpack, mostly because concentration in snow are generally quite low compared to those in river water. The remainder of the increased flux must be due to the mobilization of PFCs by the high flow conditions prevalent during snowmelt. Run-off behavior was clearly dependent on perfluoroalkyl chain length: Dilution with relatively clean snowmelt water caused a drop in the river water concentrations of short-chain PFCs at high flow during early melting. This prevented an early concentration peak of those water-soluble PFCs within the stream, as could have been expected in response to their early release from a melting snowpack. Instead, concentrations of particle-associated long-chain PFCs in creek water peaked early in the melt, presumably because high flow mobilized contaminated particles from impervious surfaces in the more urbanized areas of the watershed. The ability to enter the subsurface and deeper groundwater aquifers increased

  15. Improvement of the chromatographic separation performance of an imidazolium ionic liquid functionalized silica column by in situ anion-exchange with dodecyl sulfonate and dodecylbenzene sulfonate anions.

    PubMed

    Sun, Min; Feng, Juanjuan; Chen, Wenjie; Li, Leilei; Duan, Huimin; Luo, Chuannan

    2014-06-01

    The anionic part of ionic liquids can provide additional interactions during chromatographic separations. In this work, the chromatographic separation performance of a silica column functionalized with 1-propyl-3-methylimidazolium chloride ionic liquid was improved by in situ anion-exchange from chloride anions to dodecyl sulfonate anions and dodecylbenzene sulfonate anions. The separation performances of these ionic liquid functionalized phases were investigated and compared with each other using polycyclic aromatic hydrocarbons, phthalates, parabens, and phenols as model compounds. Results indicated that the new columns presented a better chromatographic separation than the original one. This was ascribed retention mechanism from organic anions. The introduction of dodecyl sulfonate anions increased the hydrophobicity of stationary phase. Furthermore, the phenyl groups of dodecylbenzene sulfonate anions could provide an enhanced selectivity to aromatic compounds such as polycyclic aromatic hydrocarbons by π-π interactions. Analysis repeatability of the new columns was satisfactory (RSD of retention time, 0.10-0.40%; RSD of peak area, 0.66-0.84%).

  16. Enantioselective conjugate addition of nitroalkanes to vinyl sulfone: an organocatalytic access to chiral amines.

    PubMed

    Zhu, Qiang; Lu, Yixin

    2009-04-16

    Organocatalytic asymmetric conjugate addition of nitroalkanes to vinyl sulfone mediated by cinchona alkaloid-derived thiourea catalyst afforded the desired Michael product with good enantioselectivity. The described method, in combination with ready desulfonation, represents a novel approach to access alpha-alkylated chiral amines.

  17. Constructing proton-conductive highways within an ionomer membrane by embedding sulfonated polymer brush modified graphene oxide

    NASA Astrophysics Data System (ADS)

    Zhao, Liping; Li, Yifan; Zhang, Haoqin; Wu, Wenjia; Liu, Jindun; Wang, Jingtao

    2015-07-01

    Sulfonated polymer brush modified graphene oxide (SP-GO) fillers with controllable brush length are synthesized via the facile distillation-precipitation polymerization, and then incorporated into sulfonated poly(ether ether ketone) (SPEEK) matrix to fabricate composite membranes. The influences of SP-GO upon the microstructures, including thermal and mechanical properties, water uptake/swelling, proton conduction, H2 permeability and single PEMFC performances of composite membranes are intensively investigated. It is found that the SP-GO fillers are uniformly dispersed and tend to lie perpendicularly to the cross-section surface of the whole membrane, which allow SP-GO fillers creating inter-connected and broad ionic pathways through the sulfonic acid groups in polymer brushes. Meanwhile, the SP-GO fillers connect the ionic clusters in SPEEK matrix via interfacial interactions. In such a way, proton-transfer highways are constructed along the SPEEK/SP-GO interface, which lower the proton transfer activation energy and enhance the proton conductivities of the composite membranes under both hydrated and anhydrous conditions. Furthermore, elevating the brush length on SP-GO could further enhance the proton conductivity. Compared to SPEEK control membrane, a 95.5% increase in hydrated conductivity, an 178% increase in anhydrous conductivity and a 37% increase in maximum power density are obtained for the optimal composite membrane.

  18. Decline in perfluorooctane sulfonate and perfluorooctanoate serum concentrations in an Australian population from 2002 to 2011

    PubMed Central

    Toms, L.-M.L.; Thompson, J.; Rotander, A.; Hobson, P.; Calafat, A.M.; Kato, K.; Ye, X.; Broomhall, S.; Harden, F.; Mueller, J.F.

    2016-01-01

    Some perfluoroalkyl and polyfluoroalkyl substances (PFASs) have become widespread pollutants detected in human and wildlife samples worldwide. The main objective of this study was to assess temporal trends of PFAS concentrations in human blood in Australia over the last decade (2002–2011), taking into consideration age and sex trends. Pooled human sera from 2002/03 (n = 26); 2008/09 (n = 24) and 2010/11 (n = 24) from South East Queensland, Australia were obtained from de-identified surplus pathology samples and compared with samples collected previously from 2006/07 (n = 84). A total of 9775 samples in 158 pools were available for an assessment of PFASs. Stratification criteria included sex and age: <16 years (2002/03 only); 0–4 (2006/07, 2008/09, 2010/11); 5–15 (2006/07, 2008/09, 2010/11); 16–30; 31–45; 46–60; and >60 years (all collection periods). Sera were analyzed using on-line solid-phase extraction coupled to high-performance liquid chromatography–isotope dilution-tandem mass spectrometry. Perfluorooctane sulfonate (PFOS) was detected in the highest concentrations ranging from 5.3–19.2 ng/ml (2008/09) to 4.4–17.4 ng/ml (2010/11). Perfluorooctanoate (PFOA) was detected in the next highest concentration ranging from 2.8–7.3 ng/ml (2008/09) to 3.1–6.5 ng/ml (2010/11). All other measured PFASs were detected at concentrations <1 ng/ml with the exception of perfluorohexane sulfonate which ranged from 1.2–5.7 ng/ml (08/09) and 1.4–5.4 ng/ml (10/11). The mean concentrations of both PFOS and PFOA in the 2010/11 period compared to 2002/03 were lower for all adult age groups by 56%. For 5–15 year olds, the decrease was 66% (PFOS) and 63% (PFOA) from 2002/03 to 2010/11. For 0–4 year olds the decrease from 2006/07 (when data were first available for this age group) was 50% (PFOS) and 22% (PFOA). This study provides strong evidence for decreasing serum PFOS and PFOA concentrations in an Australian population from 2002 through 2011. Age trends

  19. Sulfonated guaianolides from Saussurea lappa.

    PubMed

    Wang, Fei; Xie, Zheng-Hong; Gao, Yuan; Xu, Yao; Cheng, Xue-Lian; Liu, Ji-Kai

    2008-06-01

    Two new guaiane-type sesquiterpene lactones with an unusual sulfonic acid group, sulfocostunolide A (1) and sulfocostunolide B (2), were isolated from the roots of Saussurea lappa. Their structures were elucidated on the basis of extensive spectroscopic analysis.

  20. Separation of oil-soluble sulfonates from sulfonated oils

    SciTech Connect

    Ul'yanenko, V.I.; Yur'eva, N.P.; Sergeev, V.P.

    1987-01-01

    The authors aimed at developing a method for the complete recovery, from oil solutions, of oil-water-soluble sulfonates meeting the specifications, along with oils at least 99% pure, suitable for further processing. As the starting material the authors used an experimental batch of sulfonated and neutralized distillate lube stocks produced by selective solvent treatment. In determining the optimal extraction parameters, the authors investigated the influence of the solvent to original feed (S:F) weight ratio and the influence of the isopropyl alcohol (IPA) concentration on the composition of the sulfonates and oils recovered at 60/sup 0/C with a settling time of 2 h. The optimal conditions for two-stage extraction were found through a study of the influence of temperature and settling time on the compositions of the sulfonates and oils with S:F = 1.2:1 and with an IPA concentration of 40%. The process technology for two-stage recovery of oils and sulfonates from oil solutions was worked out in a pilot unit.

  1. Crystal structure of di-methyl-formamidium bis-(tri-fluoro-methane-sulfon-yl)amide: an ionic liquid.

    PubMed

    Cardenas, Allan Jay P; O'Hagan, Molly

    2016-09-01

    At 100 K, the title mol-ecular salt, C3H8NO(+)·C2F6NO4S2(-), has ortho-rhom-bic (P212121) symmetry; the amino H atom of bis-(tri-fluoro-methane-sulfon-yl)amine (HNTf2) was transferred to the basic O atom of di-methyl-formamide (DMF) when the ionic liquid components were mixed. The structure displays an O-H⋯N hydrogen bond, which links the cation to the anion, which is reinforced by a non-conventional C-H⋯O inter-action, generating an R2(2)(7) loop. A further very weak C-H⋯O inter-action generates an [001] chain.

  2. Microbial characterization and degradation of linear alkylbenzene sulfonate in an anaerobic reactor treating wastewater containing soap powder.

    PubMed

    Carosia, Mariana Fronja; Okada, Dagoberto Yukio; Sakamoto, Isabel Kimiko; Silva, Edson Luiz; Varesche, Maria Bernadete Amâncio

    2014-09-01

    The aim of this study was to evaluate the removal of linear alkylbenzene sulfonate (LAS) in an anaerobic fluidized bed reactor (AFBR) treating wastewater containing soap powder as LAS source. At Stage I, the AFBR was fed with a synthetic substrate containing yeast extract and ethanol as carbon sources, and without LAS; at Stage II, soap powder was added to this synthetic substrate obtaining an LAS concentration of 14 ± 3 mg L(-1). The compounds of soap powder probably inhibited some groups of microorganisms, increasing the concentration of volatile fatty acids (VFA) from 91 to 143 mg HAc L(-1). Consequently, the LAS removal rate was 48 ± 10% after the 156 days of operation. By sequencing, 16S rRNA clones belonging to the phyla Proteobacteria and Synergistetes were identified in the samples taken at the end of the experiment, with a remarkable presence of Dechloromonas sp. and Geobacter sp.

  3. Oxidative sulfonation of benzene

    SciTech Connect

    Kashnikova, L.V.; Golodov, V.A.; Vozdvizhenskii, V.F.; Levintova, T.D.

    1988-02-10

    The oxidative sulfonation of benzene with sulfur dioxide was studied in the presence of copper(II) chloride. The relation of the reaction rate to the amount of sulfur dioxide absorbed and the relation of the initial reaction rate to the benzene concentration is shown. With rise in benzene concentration, the initial reaction rate rose linearly and the amount of SO/sub 2/ absorbed remained practically constant. A mechanism was proposed that included the stage of the successive formation of an intermediate containing Cu(II) with benzene and sulfur dioxide and its subsequent redox breakdown to the final products as a result of attack by a Cu(II) benzene complex.

  4. An Assessment of the Exposure of Americans to Perflourooctane Sulfonate: A Comparison of Estimated Intake with Values Inferred from NHANES Data

    EPA Science Inventory

    To better understand human exposure to perfluorinated compounds (PFCs), a model that assesses exposure to perfluorooctane sulfonate (PFOS) and its precursors from both an intake and a body burden perspective and combines the two with a simple pharmacokinetic (PK) model is demonst...

  5. Extreme ultraviolet (EUV) degradation of poly(olefin sulfone)s: Towards applications as EUV photoresists

    NASA Astrophysics Data System (ADS)

    Lawrie, Kirsten; Blakey, Idriss; Blinco, James; Gronheid, Roel; Jack, Kevin; Pollentier, Ivan; Leeson, Michael J.; Younkin, Todd R.; Whittaker, Andrew K.

    2011-02-01

    Poly(olefin sulfone)s, formed by the reaction of sulfur dioxide (SO 2) and an olefin, are known to be highly susceptible to degradation by radiation and thus have been identified as candidate materials for chain scission-based extreme ultraviolet lithography (EUVL) resist materials. In order to investigate this further, the synthesis and characterisation of two poly(olefin sulfone)s namely poly(1-pentene sulfone) (PPS) and poly(2-methyl-1-pentene sulfone) (PMPS), was achieved and the two materials were evaluated for possible chain scission EUVL resist applications. It was found that both materials possess high sensitivities to EUV photons; however; the rates of outgassing were extremely high. The only observed degradation products were found to be SO 2 and the respective olefin suggesting that depolymerisation takes place under irradiation in a vacuum environment. In addition to depolymerisation, a concurrent conversion of SO 2 moieties to a sulfide phase was observed using XPS.

  6. Hydrogen Bonding Cluster-Enabled Addition of Sulfonic Acids to Haloalkynes: Access to Both (E)- and (Z)-Alkenyl Sulfonates.

    PubMed

    Zeng, Xiaojun; Liu, Shiwen; Shi, Zhenyu; Xu, Bo

    2016-10-07

    We developed an efficient synthesis of alkenyl sulfonates via hydrogen bonding cluster-enabled addition of sulfonic acids to haloalkynes. The reactivity of sulfonic acids could be significantly enhanced in the presence of strong hydrogen bonding donors. This metal-free method results in good chemical yields for a wide range of haloalkyne substrates and demonstrates good functional group tolerance. What is more, we can control the stereoselectivity of addition (cis vs trans) by varying the steric bulk of the sulfonic acid.

  7. Colon Necrosis Due to Sodium Polystyrene Sulfonate with and without Sorbitol: An Experimental Study in Rats

    PubMed Central

    Ayoub, Isabelle; Oh, Man S.; Gupta, Raavi; McFarlane, Michael; Babinska, Anna; Salifu, Moro O.

    2015-01-01

    Introduction Based on a single rat study by Lillemoe et al, the consensus has been formed to implicate sorbitol rather than sodium polystyrene sulfonate (SPS) as the culprit for colon necrosis in humans treated with SPS and sorbitol. We tested the hypothesis that colon necrosis by sorbitol in the experiment was due to the high osmolality and volume of sorbitol rather than its chemical nature. Methods 26 rats underwent 5/6 nephrectomy. They were divided into 6 groups and given enema solutions under anesthesia (normal saline, 33% sorbitol, 33% mannitol, SPS in 33% sorbitol, SPS in normal saline, and SPS in distilled water). They were sacrificed after 48 hours of enema administration or earlier if they were very sick. The gross appearance of the colon was visually inspected, and then sliced colon tissues were examined under light microscopy. Results 1 rat from the sorbitol and 1 from the mannitol group had foci of ischemic colonic changes. The rats receiving SPS enema, in sorbitol, normal saline, distilled water, had crystal deposition with colonic necrosis and mucosal erosion. All the rats not given SPS survived until sacrificed at 48 h whereas 11 of 13 rats that received SPS in sorbitol, normal saline or distilled water died or were clearly dying and sacrificed sooner. There was no difference between sorbitol and mannitol when given without SPS. Conclusions In a surgical uremic rat model, SPS enema given alone or with sorbitol or mannitol seemed to cause colon necrosis and high mortality rate, whereas 33% sorbitol without SPS did not. PMID:26413782

  8. Synthesis and characterization of sulfonated poly(ether sulfone)s containing mesonaphthobifluorene for polymer electrolyte membrane fuel cell.

    PubMed

    Lim, Youngdon; Seo, Dongwan; Lee, Soonho; Hossain, Md Awlad; Lim, Jinseong; Lee, Sangyoung; Hong, Taehoon; Kim, Whangi

    2014-10-01

    The novel sulfonated poly(ether sulfone)s containing mesonaphthobifluorene (MNF) moiety were synthesized and characterized their properties. The prepared polymers have highly conjugated aromatic structure due to the MNF group which is an allotrope of carbon and one atom thick planar sheets of sp2-bonded carbon atoms. Poly(ether sulfone)s bearing tetraphenylethylene on polymer backbone were synthesized by polycondensation and followed intra-cyclization from tetraphenylethylene to form MNF by Friedel-craft reaction with Lewis acid (FeCl3). The sulfonation was performed selectively on MNF units with conc. sulfuric acid. The structural properties of the sulfonated polymers were investigated by 1H-NMR spectroscopy. The membranes were studied by ion exchange capacity (IEC), water uptake, and proton conductivity. The synthesized polymer electrolyte membranes showed better thermal and dimensional stabilities owing to the inducted highly conjugated aromatic structure in the polymer backbone. The water uptake of the synthesized membranes ranged from 23-52%, compared with 32.13% for Nafion 211 at 80 degrees C. The synthesized membranes exhibited proton conductivities (80 degrees C, RH 90%) of 74.6-100.4 mS/cm, compared with 102.7 mS/cm for Nafion 211.

  9. β-Lactamase Inhibition by 7-Alkylidenecephalosporin Sulfones: Allylic Transposition and Formation of an Unprecedented Stabilized Acyl-Enzyme

    PubMed Central

    Rodkey, Elizabeth A.; McLeod, David C.; Bethel, Christopher R.; Smith, Kerri M.; Xu, Yan; Chai, Weirui; Che, Tao; Carey, Paul R.; Bonomo, Robert A.; van den Akker, Focco; Buynak, John D.

    2014-01-01

    The inhibition of the class A SHV-1 β-lactamase by 7-(tert-butoxycarbonyl)methylidenecephalosporin sulfone was examined kinetically, spectroscopically, and crystallographically. An 1.14Å X-ray crystal structure shows that the stable acyl-enzyme, which incorporates an eight-membered ring, is a covalent derivative of Ser70 linked to the 7-carboxy group of 2-H-5,8-dihydro-1,1-dioxo-1,5-thiazocine-4,7-dicarboxylic acid. A cephalosporin-derived enzyme complex of this type is unprecedented and the rearrangement leading to its formation may offer new possibilities for inhibitor design. The observed acyl-enzyme derives its stability from the resonance stabilization conveyed by the β-aminoacrylate (i.e. vinylogous urethane) functionality as there is relatively little interaction of the eight-membered ring with active site residues. Two mechanistic schemes are proposed, differing in whether, subsequent to acylation of the active site serine and opening of the β-lactam, the resultant dihydrothiazine fragments on its own, or is assisted by an adjacent nucleophilic atom, in the form of the carbonyl oxygen of the C7 tert-butyloxycarbonyl group. This compound was also found to be a submicromolar inhibitor of the class C ADC-7 and PDC-3 β-lactamases. PMID:24219313

  10. Effect of linear alkylbenzene sulfonates on the growth of aerobic heterotrophic cultivable bacteria isolated from an agricultural soil.

    PubMed

    Sánchez-Peinado, María del Mar; González-López, Jesús; Rodelas, Belén; Galera, Vanesa; Pozo, Clementina; Martínez-Toledo, María Victoria

    2008-08-01

    An enrichment culture technique was used to isolate soil bacteria capable of growing in the presence of two different concentrations of linear alkylbenzene sulfonates (LAS) (10 and 500 microg ml(-1)). Nine bacterial strains, representatives of the major colony types of aerobic heterotrophic cultivable bacteria in the enriched samples, were isolated and subsequently identified by PCR-amplification and partial sequencing of the 16S rRNA gene. Amongst the isolates, strains LAS05 (Pseudomonas syringae), LAS06 (Staphylococcus epidermidis), LAS07 (Delftia tsuruhatensis), LAS08 (Staphylococcus epidermidis) and LAS09 (Enterobacter aerogenes), were able to grow in pure culture in dialysed soil media amended with LAS (50 microg ml(-1)). The three Gram-negative strains grew to higher cell numbers in the presence of 50 microg ml(-1) of LAS, compared to LAS-unamended dialysed soil medium, and were selected for further testing of their ability to use LAS as carbon source. However, HPLC analysis of culture supernatants showed that the three strains can tolerate but not degrade LAS when grown in pure cultures. A higher concentration of soluble phosphates was recorded in dialysed soil media amended with LAS (50 microg ml(-1)) compared to unamended control media, suggesting an effect of the surfactant that enhanced the bioavailability of P from soil. The presence of LAS at a concentration of 50 microg ml(-1) had an important impact on growth of selected aerobic heterotrophic soil bacteria, a deleterious effect which may be relevant for the normal function and evolution of agricultural soil.

  11. Synthesis of a Sulfonated Two-Dimensional Covalent Organic Framework as an Efficient Solid Acid Catalyst for Biobased Chemical Conversion.

    PubMed

    Peng, Yongwu; Hu, Zhigang; Gao, Yongjun; Yuan, Daqiang; Kang, Zixi; Qian, Yuhong; Yan, Ning; Zhao, Dan

    2015-10-12

    Because of limited framework stability tolerance, de novo synthesis of sulfonated covalent organic frameworks (COFs) remains challenging and unexplored. Herein, a sulfonated two-dimensional crystalline COF, termed TFP-DABA, was synthesized directly from 1,3,5-triformylphloroglucinol and 2,5-diaminobenzenesulfonic acid through a previously reported Schiff base condensation reaction, followed by irreversible enol-to-keto tautomerization, which strengthened its structural stability. TFP-DABA is a highly efficient solid acid catalyst for fructose conversion with remarkable yields (97 % for 5-hydroxymethylfurfural and 65 % for 2,5-diformylfuran), good chemoselectivity, and good recyclability. The present study sheds light on the de novo synthesis of sulfonated COFs as novel solid acid catalysts for biobased chemical conversion.

  12. Self-organization of surfactant molecules on solid surface: an STM study of sodium alkyl sulfonates [rapid communication

    NASA Astrophysics Data System (ADS)

    Yin, Xiu-Li; Wan, Li-Jun; Yang, Zheng-Yu; Yu, Jia-Yong

    2005-02-01

    Adsorption and self-organization of sodium alkyl sulfonates (STS and SHS) on HOPG have been studied by using in situ scanning tunneling microscopy (STM). Both SHS and STS molecules adsorb on HOPG surface and form long-range well-ordered monolayers. The molecular rows and the axes of alkyl chain of the molecules cross each other at angles of 60° and 90° in the STS and SHS layers, respectively. Molecular details such as sulfonate functional group (head) and alkyl chain are clearly imaged. The neighboring molecules in different rows form a "head to head" configuration. Structural models for the molecular arrangement of the two adlayers are proposed.

  13. Proline is a protein solubilizing solute.

    PubMed

    Samuel, D; Kumar, T K; Jayaraman, G; Yang, P W; Yu, C

    1997-02-01

    The effect of proline on the prevention of trichloroacetic acid (TCA)-induced protein precipitation is studied. It is found that proline at high concentrations (> 4.0 M) completely prevents TCA-induced precipitation of hen egg white lysozyme. Other osmolytes such as ethylene glycol, glycerol and sucrose fail to prevent the TCA-induced precipitation of lysozyme. Viscosity and 1-anilino-8-naphthalene sulphonic acid binding experiments suggest that proline at high concentration forms an ordered supramolecular assembly. Proline is shown to increase the solubility of protein due to formation of such higher order assemblies. A model of the supra-molecular assembly of proline is proposed and a possible in vivo role of the increased levels of proline under water stress is discussed.

  14. Sulfonated polyphenylene polymers

    DOEpatents

    Cornelius, Christopher J.; Fujimoto, Cy H.; Hickner, Michael A.

    2007-11-27

    Improved sulfonated polyphenylene compositions, improved polymer electrolyte membranes and nanocomposites formed there from for use in fuel cells are described herein. The improved compositions, membranes and nanocomposites formed there from overcome limitations of Nafion.RTM. membranes.

  15. Penicillanic acid sulfone: an unexpected isotope effect in the interaction of 6 alpha- and 6 beta-monodeuterio and of 6,6-dideuterio derivatives with RTEM beta-lactamase from Escherichia coli.

    PubMed

    Brenner, D G; Knowles, J R

    1981-06-23

    Penicillanic acid sulfone (1) is both a substrate and an inactivator of the RTEM beta-lactamase. About 7000 hydrolytic events occur before enzyme inactivation. The 6,6-dideuterio sulfone shows a 3-fold acceleration of both the hydrolysis reaction and the enzyme inactivation. The kinetic and spectroscopic results are nicely accommodated by a scheme in which a transiently stable intermediate is formed in an isotopically sensitive step. The deuterated material partitions less readily toward this transiently stable intermediate by virtue of a primary isotope effect, and more enzyme is then available for the hydrolysis and inactivation pathways. Use of the stereospecifically monodeuterated sulfones shows that the 6 beta hydrogen is preferentially abstracted in the formation of the transiently stable intermediate and allows a detailed picture of the interaction of the sulfone and the beta-lactamase to be drawn. The crystal structures of both the labeled and unlabeled compounds are reported.

  16. Crystal structure of zwitterionic bisimidazolium sulfonates

    NASA Astrophysics Data System (ADS)

    Kohmoto, Shigeo; Okuyama, Shinpei; Yokota, Nobuyuki; Takahashi, Masahiro; Kishikawa, Keiki; Masu, Hyuma; Azumaya, Isao

    2012-05-01

    Crystal structures of three zwitterionic bisimidazolium salts 1-3 in which imidazolium sulfonate moieties were connected with aromatic linkers, p-xylylene, 4,4'-dimethylenebiphenyl, and phenylene, respectively, were examined. The latter two were obtained as hydrates. An S-shaped molecular structure in which the sulfonate moiety was placed on the imidazolium ring was observed for 1. A helical array of hydrated water molecules was obtained for 2 while a linear array of hydrated water molecules was observed for 3.

  17. Phytoremediation of sulfonated Remazol Red dye and textile effluents by Alternanthera philoxeroides: An anatomical, enzymatic and pilot scale study.

    PubMed

    Rane, Niraj R; Chandanshive, Vishal V; Watharkar, Anuprita D; Khandare, Rahul V; Patil, Tejas S; Pawar, Pankaj K; Govindwar, Sanjay P

    2015-10-15

    Alternanthera philoxeroides Griseb. a macrophyte was found to degrade a highly sulfonated textile dye Remazol Red (RR) completely within 72 h at a concentration of 70 mg L(-1). An induction in the activities of azoreductase and riboflavin reductase was observed in root and stem tissues; while the activities of lignin peroxidase, laccase and DCIP reductase were induced in leaf tissues. Some enzymes namely tyrosinase, veratryl alcohol oxidase, catalase and superoxide dismutase displayed an increase in their activity in all the tissues in response of 72 h exposure to Remazol Red. There was a marginal reduction in contents of chlorophyll a (20%), chlorophyll b (5%) and carotenoids (16%) in the leaves when compared to control plants. A detailed anatomical study of the stem during uptake and treatment revealed a stepwise mechanism of dye degradation. UV-vis spectrophotometric and high performance thin layer chromatographic analyses confirmed the removal of parent dye from solution. Based on the enzymes activities and gas chromatography-mass spectroscopic analysis of degradation products, a possible pathway of phytotransformation of RR was proposed which revealed the formation of 4-(phenylamino)-1,3,5-triazin-2-ol, naphthalene-1-ol and 3-(ethylsulfonyl)phenol. Toxicity study on Devario aequipinnatus fishes showed that the anatomy of gills of fishes exposed to A. philoxeroides treated RR was largely protected. The plants were further explored for rhizofiltration experiments in a pilot scale reactor. A. philoxeroides could decolorize textile industry effluent of varying pH within 96 h of treatment which was evident from the significant reductions in the values of American dye manufacturers' institute color, chemical oxygen demand, biological oxygen demand, total dissolved and total suspended solids.

  18. Multitargeting by curcumin as revealed by molecular interaction studies.

    PubMed

    Gupta, Subash C; Prasad, Sahdeo; Kim, Ji Hye; Patchva, Sridevi; Webb, Lauren J; Priyadarsini, Indira K; Aggarwal, Bharat B

    2011-11-01

    Curcumin (diferuloylmethane), the active ingredient in turmeric (Curcuma longa), is a highly pleiotropic molecule with anti-inflammatory, anti-oxidant, chemopreventive, chemosensitization, and radiosensitization activities. The pleiotropic activities attributed to curcumin come from its complex molecular structure and chemistry, as well as its ability to influence multiple signaling molecules. Curcumin has been shown to bind by multiple forces directly to numerous signaling molecules, such as inflammatory molecules, cell survival proteins, protein kinases, protein reductases, histone acetyltransferase, histone deacetylase, glyoxalase I, xanthine oxidase, proteasome, HIV1 integrase, HIV1 protease, sarco (endo) plasmic reticulum Ca(2+) ATPase, DNA methyltransferases 1, FtsZ protofilaments, carrier proteins, and metal ions. Curcumin can also bind directly to DNA and RNA. Owing to its β-diketone moiety, curcumin undergoes keto-enol tautomerism that has been reported as a favorable state for direct binding. The functional groups on curcumin found suitable for interaction with other macromolecules include the α, β-unsaturated β-diketone moiety, carbonyl and enolic groups of the β-diketone moiety, methoxy and phenolic hydroxyl groups, and the phenyl rings. Various biophysical tools have been used to monitor direct interaction of curcumin with other proteins, including absorption, fluorescence, Fourier transform infrared (FTIR) and circular dichroism (CD) spectroscopy, surface plasmon resonance, competitive ligand binding, Forster type fluorescence resonance energy transfer (FRET), radiolabeling, site-directed mutagenesis, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), immunoprecipitation, phage display biopanning, electron microscopy, 1-anilino-8-naphthalene-sulfonate (ANS) displacement, and co-localization. Molecular docking, the most commonly employed computational tool for calculating binding affinities and predicting

  19. MATERNAL AND DEVELOPMENTAL TOXICITY OF PERFLUOROOCTANE SULFONATE IN THE RAT

    EPA Science Inventory

    MATERNAL AND DEVELOPMENTAL TOXICITY OF PERFLUOROOCTANE SULFONATE IN THE RAT.
    C. Lau and J.M. Rogers, Reproductive Toxicology Division, NHEERL, ORD, USEPA, Research Triangle Park, NC, USA

    Perfluorooctane sulfonate (PFOS), an environmentally persistent compound used ...

  20. Radiation grafted and sulfonated (FEP-g-polysterene) - An alternative to perfluorinated membranes for PEM fuel cells?

    NASA Astrophysics Data System (ADS)

    Buechi, F. N.; Gupta, B.; Rouilly, M.; Hauser, P. C.; Chapiro, A.; Scherer, G. G.

    Partially fluorinated proton exchange membranes (PEMs) were synthesized for fuel cell applications by simultaneous radiation grafting of styrene on FEP films followed by sulfonation. Properties of the synthesized membranes can be tailored by varying the degree of grafting and crosslinking. The performance of these membranes was tested in H2/O2 fuel cells. Long time testing showed steady performance for high grafted membranes over periods of more than 300 h at a cell temperature of 60 C. Low grafted membranes and the Morgane CDS membrane showed considerable decay of cell power on the same time scale. A fast degradation of all membranes occurred at a cell temperature of 80 C. It is noted that grafting in film form makes this process a potentially cheap and easy technique for the preparation of solid polymer fuel cell electrolytes.

  1. Production and Application of Lignosulfonates and Sulfonated Lignin.

    PubMed

    Aro, Thomas; Fatehi, Pedram

    2017-03-02

    Lignin is the largest reservoir of aromatic compounds on earth and has great potential to be used in many industrial applications. Alternative methods to produce lignosulfonates from spent sulfite pulping liquors and kraft lignin from black liquor of kraft pulping process are critically reviewed herein. Furthermore, options to increase the sulfonate contents of lignin-based products are outlined and the industrial attractiveness of them is evaluated. This evaluation includes sulfonation and sulfomethylation of lignin. To increase the sulfomethylation efficiency of lignin, various scenarios, including hydrolysis, oxidation, and hydroxymethylation, were compared. The application of sulfonated lignin-based products is assessed and the impact of the properties of these products on the characteristics of their end-use application is critically evaluated. Sulfonated lignin-based products have been used as dispersants in cement admixtures and dye solutions more than other applications, and their molecular weight and degree of sulfonation were crucial in determining their efficiency. The use of lignin-based sulfonated products in composites may result in an increase in the hydrophilicity of some composites, but the sulfonated products may need to be desulfonated with an alkali and/or oxygen prior to their use in composites. To be used as a flocculant, sulfonated lignin-based products may need to be cross-linked to increase their molecular weight. The challenges associated with the use of lignin-based products in these applications are comprehensively discussed herein.

  2. Sulfonic acid-functionalized silica-coated magnetic nanoparticles as an efficient reusable catalyst for the synthesis of 1-substituted 1H-tetrazoles under solvent-free conditions.

    PubMed

    Naeimi, Hossein; Mohamadabadi, Samaneh

    2014-09-14

    Regarding green chemistry goals, silica-coated magnetite nanoparticles open up a new avenue to introduce a very useful and efficient system for facilitating catalyst recovery in different organic reactions. Therefore, in this paper the preparation of sulfonic acid-functionalized silica-coated magnetic nanoparticles with core-shell structure (Fe3O4@silica sulfonic acid) is presented by using Fe3O4 spheres as the core and silica sulfonic acid nanoparticles as the shell. The catalyst was characterized by infrared spectroscopy, scanning electron microscopy, X-ray diffraction analysis, dynamic light scattering, thermogravimetric analysis and vibrating sample magnetometry. Nanocatalyst can be recovered using an external magnet and reused for subsequent reactions 6 times without noticeable deterioration in catalytic activity.

  3. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  4. 40 CFR 721.5425 - α-Olefin sulfonate, potassium salts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false α-Olefin sulfonate, potassium salts... Substances § 721.5425 α-Olefin sulfonate, potassium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as an α-olefin sulfonate, potassium salt...

  5. 40 CFR 721.5425 - α-Olefin sulfonate, potassium salts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false α-Olefin sulfonate, potassium salts... Substances § 721.5425 α-Olefin sulfonate, potassium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as an α-olefin sulfonate, potassium salt...

  6. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  7. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  8. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  9. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  10. 40 CFR 721.5425 - α-Olefin sulfonate, potassium salts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false α-Olefin sulfonate, potassium salts... Substances § 721.5425 α-Olefin sulfonate, potassium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as an α-olefin sulfonate, potassium salt...

  11. 40 CFR 721.5425 - α-Olefin sulfonate, potassium salts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false α-Olefin sulfonate, potassium salts... Substances § 721.5425 α-Olefin sulfonate, potassium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as an α-olefin sulfonate, potassium salt...

  12. 40 CFR 721.5425 - α-Olefin sulfonate, potassium salts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false α-Olefin sulfonate, potassium salts... Substances § 721.5425 α-Olefin sulfonate, potassium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as an α-olefin sulfonate, potassium salt...

  13. Vinyl sulfone silica: application of an open preactivated support to the study of transnitrosylation of plant proteins by S-nitrosoglutathione

    PubMed Central

    2013-01-01

    Background S-nitrosylaton is implicated in the regulation of numerous signaling pathways with a diversity of regulatory roles. The high lability of the S-NO bond makes the study of proteins regulated by S-nitrosylation/denitrosylation a challenging task and most studies have focused on already S-nitrosylated proteins. We hypothesize that: i) S-nitrosoglutathione (GSNO) transnitrosylation is a feasible mechanism to account for the physiological S-nitrosylation of rather electropositive sulfur atoms from proteins, ii) affinity chromatography is a suitable approach to isolate proteins that are prone to undergo S-transnitrosylation and iii) vinyl sulfone silica is a suitable chromatographic bead. Results The combination of vinyl sulfone silica with GSNO yielded an affinity resin that withstood high ionic strength without shrinking or deforming and that it was suitable to isolate potential GSNO transnitrosylation target candidates. Fractions eluted at 1500 mM NaCl resulted in a symmetrical peak for both, protein and S-nitrosothiols, supporting the idea of transnitrosylation by GSNO as a selective process that involves strong and specific interactions with the target protein. Proteomic analysis led to the identification of 22 physiological significant enzymes that differ with the tissue analyzed, being regulatory proteins the most abundant group in hypocotyls. The identification of chloroplastidic FBPase, proteasome, GTP-binding protein, heat shock Hsp70, syntaxin, catalase I, thioredoxin peroxidase and cytochrome P450 that have already been reported as S-nitrosylated by other techniques can be considered as internal positive controls that validate our experimental approach. An additional validation was provided by the prediction of the S-nitrosylation sites in 19 of the GSNO transnitrosylation target candidates. Conclusions Vinyl sulfone silica is an open immobilization support that can be turned ad hoc and in a straightforward manner into an affinity resin. Its

  14. Perfluorooctane sulfonate (PFOS) depletion in beef cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perfluorooctane sulfonate (PFOS) is an industrial chemical that is used as a surfactant in several manufactured consumer products but is also a breakdown product from other chemical surfactants. As a result of its extensive use, PFOS is ubiquitous in the environment and is often detected in biosoli...

  15. Identification, Tissue Distribution, and Bioaccumulation Potential of Cyclic Perfluorinated Sulfonic Acids Isomers in an Airport Impacted Ecosystem.

    PubMed

    Wang, Yuan; Vestergren, Robin; Shi, Yali; Cao, Dong; Xu, Lin; Cai, Yaqi; Zhao, Xiaoli; Wu, Fengchang

    2016-10-18

    The use of cyclic perfluoroalkyl acids as anticorrosive agents in hydraulic fluids remains a poorly characterized source of organofluorine compounds to the environment. Here, we investigated the presence of perfluoroethylenecyclohexanesulfonate (PFECHS) isomers in environmental samples for the first time using a combination of high resolution and tandem mass spectrometry. Five distinct peaks attributed to different isomers of PFECHS and perfluoropropylcyclopentanesulfonate (PFPCPeS) were identified in environmental samples. The sum of PFECHS and PFPCPeS isomers displayed logarithmically decreasing spatial trends in water (1.04-324 ng/L) and sediment samples (sulfonic acid group affect the bioaccumulation potential of cyclic perfluoroalkyl acids. Based on the high mobility and moderate bioaccumulation potential of cyclic perfluorinated acids it is suggested that contamination of aquifers used for drinking water around airports may be a hitherto overlooked problem for this novel class of contaminants.

  16. Correlating electronic structure and chemical durability of sulfonated poly(arylene ether sulfone)s

    NASA Astrophysics Data System (ADS)

    Lawrence, Jimmy; Yamashita, Koichi; Yamaguchi, Takeo

    2015-04-01

    Many different proton-conducting polymeric materials have been developed for polymer electrolyte membrane fuel cells (PEMFCs). The development of perfluorosulfonic acid-based, polymer electrolyte membranes (PFSA-PEMs) was followed by aromatic hydrocarbon-based PEMs (HC-PEMs), which allow for tailored design and optimization of their molecular structures. Although many new PFSA-PEMs and HC-PEMs have shown promising proton conductivity and thermal stability, chemical degradation of these materials in an oxidizing environment remains a significant technical barrier in PEMFC development. Here, we used accelerated degradation tests and electronic structure analysis to examine the chemical stability of sulfonated poly(arylene ether sulfone) (SPES) copolymers, a highly thermally stable HC-PEM. HOMO levels, the presence of main chain-protecting steric groups, and HOMO-LUMO location along the main chain have significant effects on the chain scission modes and degradation rate of SPES copolymers. Rational design of HC-PEMs to suppress midpoint scission can open many opportunities in the development of highly robust polymer electrolytes for fuel cell and other energy storage applications.

  17. Sulfonic acid functionalized silica: an efficient heterogeneous catalyst for a three-component synthesis of 1,4-dihydropyridines under solvent-free conditions.

    PubMed

    Das, Biswanath; Suneel, Kanaparthy; Venkateswarlu, Katta; Ravikanth, Bommena

    2008-03-01

    Sulfonic acid functionalized silica catalyzed the three-component reaction of aromatic amines, alpha,beta-unsaturated aldehydes and beta-keto esters forming the corresponding 1,4-dihydropyridines in short reaction times and in high yields.

  18. Synthesization, characterization and adsorption properties of sulfonic cellulose.

    PubMed

    Shi, Wenjian; Zhou, Yan; Zhang, Yuanzhang; Li, Liang; Yang, Qinlin

    2012-01-01

    The synthesization and characterization of a new environmental functional material-sulfonic cellulose - were studied in this paper. The preparation conditions were optimized through an orthogonal experiment. The modified cellulose was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM). The adsorption rules of cationic organic pollutants and heavy metal ions by this new material were discussed. Regeneration and recycling performances of the sulfonic cellulose were also investigated. At the temperature of 323 K, sulfonic cellulose was prepared by grafting 2-acrylamido-2-methylpropane sulfonic acid (AMPS) onto alkali-treated cellulose for 4 h with the employing of ceric ammonium nitrate as initiator. The mass ratio of AMPS to cellulose was 3:1 and the concentration of ceric ammonium nitrate was 63.8 mmol/L. The sulfur content of sulfonic cellulose was 7.32 wt%. The peaks of 1,303 and 1,159 cm⁻¹ in IR suggested the existence of the sulfonic group in sulfonic cellulose. The XRD and SEM results showed that the crystallinity decreased while the specific surface area increased after modification. Batch adsorption results showed that sulfonic cellulose had a favorable adsorption capacity for model contaminants at pH 6.0-7.0. The adsorption process was endothermic and reached equilibrium in 180 min. The adsorption rules of cationic organic pollutants and heavy metal ions indicated that sulfonic cellulose had high adsorption capacity for the cationic dyes with a coplanar macromolecule structure and organic compounds carrying the amino group. Under room temperature, 1.0 mol/L HCl can be used as a desorption solution and the equilibrium adsorption capacity had little decrease (less than 7%) after six adsorption-desorption cycles.

  19. XPS Study of Sulfonated Polyaniline.

    DTIC Science & Technology

    1991-08-07

    WORK UMaT Arlington, VA 22203-17 14 ELEMENT NO. INO. NO. CCESSION No 11. TITLE (tinclude Security Clisification) "XPS STUDY OF SULFONATED POLYANILINE ...by block nvjmhet) FlIELD GROUP $u-GOP sulfonated polyaniline , x-ray photoelectron spectroscopy O(IPS) 19. ABSTRACT (Continue on reverse if nvessary...STUDY OF SULFONATED POLYANiLINE " by J. Yue, AJ. Epstein and A.G. MacDiarrnid Published in PMSE Preprints, (In Press 1991) University of Pennsylvania

  20. Vibrational frequencies and structural determinations of di-vinyl sulfone

    NASA Astrophysics Data System (ADS)

    Ellzy, Michael W.; Jensen, James O.; Kay, Jack G.

    2003-03-01

    We present a detailed analysis of the structure and infrared spectra of di-vinyl sulfone. The vibrational frequencies of the di-vinyl sulfone molecule were analyzed using standard quantum chemical techniques. Frequencies were calculated at the MP2 and DFT levels of theory using the standard 6-311G* basis set. The structural transformation of the chemical agent bis(2-chloroehtyl) sulfide (HD, mustard gas) and the related symmetry to a previously study compounds [Spectrochim. Acta Part A 55 (1999) 121; Spectrochim. Acta Part A 57 (2001) 2417] makes the symmetry of the di-vinyl sulfone molecule an interesting candidate for study. The molecule exists normally in a C2 configuration. High-energy forms of di-vinyl sulfone with CS and C1 symmetries also exist.

  1. Ionic Strength Responsive Sulfonated Polystyrene Opals.

    PubMed

    Nucara, Luca; Piazza, Vincenzo; Greco, Francesco; Robbiano, Valentina; Cappello, Valentina; Gemmi, Mauro; Cacialli, Franco; Mattoli, Virgilio

    2017-02-08

    Stimuli-responsive photonic crystals (PCs) represent an intriguing class of smart materials very promising for sensing applications. Here, selective ionic strength responsive polymeric PCs are reported. They are easily fabricated by partial sulfonation of polystyrene opals, without using toxic or expensive monomers and etching steps. The color of the resulting hydrogel-like ordered structures can be continuously shifted over the entire visible range (405-760 nm) by changing the content of ions over an extremely wide range of concentration (from about 70 μM to 4 M). The optical response is completely independent from pH and temperature, and the initial color can be fully recovered by washing the sulfonated opals with pure water. These new smart photonic materials could find important applications as ionic strength sensors for environmental monitoring as well as for healthcare screening.

  2. Preparation of tri- and difluoromethylsilanes via an unusual magnesium metal-mediated reductive tri- and difluoromethylation of chlorosilanes using tri- and difluoromethyl sulfides, sulfoxides, and sulfones.

    PubMed

    Prakash, G K Surya; Hu, Jinbo; Olah, George A

    2003-05-30

    A new and efficient method for the preparation of tri- and difluoromethylsilanes using magnesium metal-mediated reductive tri- and difluoromethylation of chlorosilanes is reported using tri- and difluoromethyl sulfides, sulfoxides, and sulfones. The byproduct of the process is diphenyl disulfide. Since phenyl trifluoromethyl sulfone, sulfoxide, and sulfide are readily prepared from trifluoromethane (CF(3)H) and diphenyl disulfide, the method can be considered to be catalytic in diphenyl disulfide for the preparation of (trifluoromethyl)trimethylsilane (TMS-CF(3)) from non-ozone-depleting trifluoromethane.

  3. Sorption of sodium dodecylbenzene sulfonate by montmorillonite.

    PubMed

    Yang, Kun; Zhu, Lizhong; Xing, Baoshan

    2007-01-01

    Sorption of linear alkylbenzene sulfonates by soils and sediments is an important process that may affect their fate, transport, toxicity and their application in remediation of contaminated soil and groundwater. In this study, batch experiments were conducted to elucidate the sorption of a widely used anionic surfactant, sodium dodecylbenzene sulfonate (SDBS), by montmorillonite. It was observed that: (i) SDBS was sorbed significantly by montmorillonite saturated with Ca(2+), but little by Na-saturated montmorillonite; (ii) the amount of SDBS sorbed by Ca(2+)-montmorillonite was enhanced by NaCl; and (iii) no significant intercalation of SDBS into Ca(2+)-montmorillonite was observed by X-ray diffraction (XRD) analysis. These results indicate that the removal of SDBS by Ca(2+)-montmorillonite was primarily attributed to the precipitation between DBS(-) and Ca(2+) in solution which was released from montmorillonite via cation exchange. These results will help us to understand the sorption behavior and environmental effects of anionic surfactants.

  4. An Introduction to Multivariate Curve Resolution-Alternating Least Squares: Spectrophotometric Study of the Acid-Base Equilibria of 8-Hydroxyquinoline-5-Sulfonic Acid

    ERIC Educational Resources Information Center

    Rodriguez-Rodriguez, Cristina; Amigo, Jose Manuel; Coello, Jordi; Maspoch, Santiago

    2007-01-01

    A spectrophotometric study of the acid-base equilibria of 8-hydroxyquinoline-5-sulfonic acid to describe the multivariate curve resolution-alternating least squares algorithm (MCR-ALS) is described. The algorithm provides a lot of information and hence is of great importance for the chemometrics research.

  5. An alternative standard for Trolox-equivalent antioxidant-capacity estimation based on thiol antioxidants. Comparative 2,2'-azinobis[3-ethylbenzothiazoline-6-sulfonic acid] decolorization and rotational viscometry study regarding hyaluronan degradation.

    PubMed

    Hrabárová, Eva; Valachová, Katarína; Rapta, Peter; Soltés, Ladislav

    2010-09-01

    Comparison of the effectiveness of antioxidant activity of three thiol compounds, D-penicillamine, reduced L-glutathione, and 1,4-dithioerythritol, expressed as a radical-scavenging capacity based on the two independent methods, namely a decolorization 2,2'-azinobis[3-ethylbenzothiazoline-6-sulfonic acid] assay and a rotational viscometry, is reported. Particular concern was focused on the testing of potential free-radical scavenging effects of thiols against hyaluronan degradation, induced by hydroxyl radicals. A promising, solvent-independent, antioxidative function of 1,4-dithioerythritol, comparable to that of a standard compound, Trolox(®), was confirmed by the 2,2'-azinobis[3-ethylbenzothiazoline-6-sulfonic acid] assay. The new potential antioxidant 1,4-dithioerythritol exhibited very good solubility in a variety of solvents (e.g., H(2)O, EtOH, and DMSO) and could be widely accepted and used as an effective antioxidant standard instead of a routinely used Trolox(®) on 2,2'-azinobis[3-ethylbenzothiazoline-6-sulfonic acid] assay.

  6. Safety assessment of xylene sulfonic acid, toluene sulfonic acid, and alkyl aryl sulfonate hydrotropes as used in cosmetics.

    PubMed

    Bergfeld, Wilma F; Belsito, Donald V; Klaassen, Curtis D; Hill, Ronald; Liebler, Daniel; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan

    2011-12-01

    Xylene sulfonic acid, toluene sulfonic acid, and alkyl aryl sulfonate hydrotropes used in cosmetics as surfactants, hydrotropes, were reviewed in this safety assessment. The similar structure, properties, functions, and uses of these ingredients enabled grouping them and using the available toxicological data to assess the safety of the entire group. The Cosmetic Ingredient Review Expert Panel reviewed relevant animal and human data related to these ingredients. The panel concluded that xylene sulfonic acid and alkyl aryl sulfonate hydrotropes are safe as cosmetic ingredients in the present practices of use and concentrations as described in this safety assessment, when formulated to be nonirritating.

  7. Modified overbased sulfonates and phenates

    SciTech Connect

    Strukl, J.S.; Watson, R.W.

    1982-05-04

    Disclosed are compositions of matter and a method for their manufacture, and lubricating oil compositions containing such compositions. The compositions of matter comprise the reaction product of basic compound comprising overbased metal sulfonate, phenate, or mixtures thereof, with acidic compound comprising organic carboxylic acid, organic carboxylic acid anhydride, phosphoric acid, phosphoric acid ester, thiophosphoric acid ester , or mixtures thereof.

  8. p-Chlorophenyl methyl sulfone

    Integrated Risk Information System (IRIS)

    p - Chlorophenyl methyl sulfone ; CASRN 98 - 57 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for No

  9. An Evaluation of a Teat Dip with Dodecyl Benzene Sulfonic Acid in Preventing Bovine Mammary Gland Infection from Experimental Exposure to Streptococcus agalactiae and Staphylococcus aureus

    PubMed Central

    Barnum, D. A.; Johnson, R. E.; Brooks, B. W.

    1982-01-01

    The effectiveness of a teat dip with dodecyl benzene sulfonic acid (1.94%) for the prevention of intramammary infections was determined in cows experimentally challenged with Streptococcus agalactiae and Staphylococcus aureus. The infection rates with Streptococcus agalactiae and Staphylococcus aureus were 62.5% and 75% in undipped quarters, 12.5% and 21.5% in dipped quarters with a reduction rate of 80% and 71% respectively. The significance of some findings in relation to mastitis control are discussed. PMID:17422110

  10. Process for sulfonation of gas oils

    SciTech Connect

    Berg, R. C.

    1980-12-23

    A process for the production of oil-soluble sulfonates from a gas oil such as a vacuum gas oil. Water-soluble sulfonic acids are separated from the effluent of the sulfonation zone, and the remainder of the effluent is then passed through a saponification zone to produce oil-soluble sulfonates which are then recovered. The remaining hydrocarbons are fractionated, with the resultant heavy fraction being passed through a reforming zone to produce additional aromatics which are then recycled to the sulfonation zone.

  11. Damage to fuel cell membranes. Reaction of HO* with an oligomer of poly(sodium styrene sulfonate) and subsequent reaction with O(2).

    PubMed

    Dockheer, Sindy M; Gubler, Lorenz; Bounds, Patricia L; Domazou, Anastasia S; Scherer, Günther G; Wokaun, Alexander; Koppenol, Willem H

    2010-10-07

    An understanding of the reactivity of oligomeric compounds that model fuel cell membrane materials under oxidative-stress conditions that mimic the fuel cell operating environment can identify material weaknesses and yield valuable insights into how a polymer might be modified to improve oxidative stability. The reaction of HO˙ radicals with a polymer electrolyte fuel cell membrane represents an initiation step for irreversible membrane oxidation. By means of pulse radiolysis, we measured k = (9.5 ± 0.6) × 10(9) M(-1) s(-1) for the reaction of HO˙ with poly(sodium styrene sulfonate), PSSS, with an average molecular weight of 1100 Da (PSSS-1100) in aqueous solution at room temperature. In the initial reaction of HO˙ with the oligomer (90 ± 10)% react by addition to form hydroxycyclohexadienyl radicals, while the remaining abstract a hydrogen to yield benzyl radicals. The hydroxycyclohexadienyl radicals react reversibly with dioxygen to form the corresponding peroxyl radicals; the second-order rate constant for the forward reaction is k(f) = (3.0 ± 0.5) × 10(7) M(-1) s(-1), and for the back reaction, we derive an upper limit for the rate constant k(r) of (4.5 ± 0.9) × 10(3) s(-1). These data place a lower bound on the equilibrium constant K of (7 ± 2) × 10(3) M(-1) at 295 K, which allows us to calculate a lower limit of the Gibbs energy for the reaction, (-21.7 ± 0.8) kJ mol(-1). At pH 1, the hydroxycyclohexadienyl radicals decay with an overall first-order rate constant k of (6 ± 1) × 10(3) s(-1) to yield benzyl radicals. The second-order rate constant for reaction of dioxygen with benzyl radicals of PSSS-1100 is k = (2-5) × 10(8) M(-1) s(-1). We discuss hydrogen abstraction from PSSS-1100 in terms of the bond dissociation energy, and relate these to relevant electrode potentials. We propose a reaction mechanism for the decay of hydroxycyclohexadienyl radicals and subsequent reaction steps.

  12. Fully Sulfonated Polyaniline (NSPAN)(We thank Mitsubishi Rayon for samples.) and Aluminum Interface: an XPS Study

    NASA Astrophysics Data System (ADS)

    Smallfield, J. A. O.; Fahlman, M.; Epstein, A. J.

    2000-03-01

    We report the results of XPS experiments in which aluminum was evaporated onto NSPAN. Data for pristine NSPAN shows two N1s peaks centered at ~399.3 eV and ~401.3 eV, with an area ratio of ~0.46:0.54. These peaks are assigned to amine and protonated imine nitrogens, respectively. The area ratio is consistent with the emeraldine salt state of polyaniline with strong localization in bipolaron form, as independently determined by magnetic studies.(W. Lee, G. Du, A.J. Epstein, S. Shimizu, T. Saitoh, and M. Uzawa, Synth. Met. 84), 807 (1997). With increasing aluminum deposition, the amine and protonated imine peak positions remain fixed, while the amine to imine ratio increases to ~0.70:0.30. This is consistent with charge donation from aluminum to NSPAN across the interface. Pristine NSPAN shows two S2p peaks centered at ~167.2 eV and ~168.5 eV in a ratio of ~0.75:0.25, each with a high binding energy shoulder, as expected for a 2p split line. These peaks are attributed to SO_3^- and SO_3H, respectively. With increasing aluminum deposition, the S2p envelope broadens, indicating a variety of chemical environments for sulfur. The possible role of hydrogen bonding to methoxy or other moities in NSPAN will be discussed.

  13. Chemical and Mechanical Degradation of Sulfonated Poly(sulfone) Membranes in Vanadium Redox Flow Batteries

    SciTech Connect

    Kim, Soowhan; Tighe, Timothy B.; Schwenzer, Birgit; Yan, Jingling; Zhang, Jianlu; Liu, Jun; Yang, Zhenguo; Hickner, Michael A.

    2011-10-01

    A sulfonated poly(sulfone) (S-Radel{reg_sign}) membrane with high proton conductivity and low vanadium ion diffusion showed high initial performance in a vanadium redox flow battery (VRFB) but suffered damage during charge/discharge cycling. The S-Radel membrane had different degradation behaviors in flow cell cycling and ex-situ vanadium ion immersion tests. The S-Radel membrane immersed in V5+ solution cracked into small pieces, but in the VRFB cell, the membrane underwent internal delamination preferentially on the side of the membrane that faced the positive electrode. A vanadium-rich interface was observed near the membrane surface that experienced delamination and Raman spectroscopic analysis of the surfaces of the membrane indicated a slightly depressed 1026 cm-1 band corresponding to the sulfonate SO2 stretch for the degraded surface. Even though the S-Radel membrane underwent severe mechanical damage during the flow cell cycling, significant chemical degradation was not obvious from the spectroscopic analyses. For the VRFB containing an S-Radel membrane, an increase in membrane resistance caused an abnormal voltage depression during the discharge cycle. The reversible increase in membrane resistance and severe mechanical degradation of the membrane during cycling may be attributed repeated formation and dissolution of particles inside the membrane. The mechanical stresses imposed by the particles coupled with a small amount of chemical degradation of the polymer by V5+, are likely degradation mechanisms of the S-Radel membrane in VRFBs under high state-of-charge conditions.

  14. p-Sulfonic Acid Calix[4]arene as an Efficient Catalyst for One-Pot Synthesis of Pharmaceutically Significant Coumarin Derivatives under Solvent-Free Condition

    PubMed Central

    Tashakkorian, Hamed; Lakouraj, Moslem Mansour; Rouhi, Mona

    2015-01-01

    One-pot and efficient protocol for preparation of some potent pharmaceutically valuable coumarin derivatives under solvent-free condition via direct coupling using biologically nontoxic organocatalyst, calix[4]arene tetrasulfonic acid (CSA), was introduced. Calix[4]arene sulfonic acid has been incorporated lately as a magnificent and recyclable organocatalyst for the synthesis of some organic compounds. Nontoxicity, solvent-free conditions, good-to-excellent yields for pharmaceutically significant structures, and especially ease of catalyst recovery make this procedure valuable and environmentally benign. PMID:26798517

  15. Sulfonated polysulfone battery membrane for use in corrosive environments

    DOEpatents

    Arnold, Jr., Charles; Assink, Roger

    1987-01-01

    For batteries containing strong oxidizing electrolyte and a membrane separating two electrolyte solutions, e.g., a zinc ferricyanide battery, an improved membrane is provided comprising an oxidative resistant, conductive, ion-selective membrane fabricated from a catenated aromatic polymer having an absence of tertiary hydrogens, e.g., a sulfonated polysulfone.

  16. 3′-Daidzein sulfonate sodium improves mitochondrial functions after cerebral ischemia/reperfusion injury

    PubMed Central

    Yuan, Wa; Chen, Qin; Zeng, Jing; Xiao, Hai; Huang, Zhi-hua; Li, Xiao; Lei, Qiong

    2017-01-01

    3′-Daidzein sulfonate sodium is a new synthetic water-soluble compound derived from daidzein (an active ingredient of the kudzu vine root). It has been shown to have a protective effect on cerebral ischemia/reperfusion injury in rats. We plan to study the mechanism of its protective effect. 3′-Daidzein sulfonate sodium was injected in rats after cerebral ischemia/reperfusion injury. Results showed that 3′-daidzein sulfonate sodium significantly reduced mitochondrial swelling, significantly elevated the mitochondrial membrane potential, increased mitochondrial superoxide dismutase and glutathione peroxidase activities, and decreased mitochondrial malondialdehyde levels. 3′-Daidzein sulfonate sodium improved the structural integrity of the blood-brain barrier and reduced blood-brain barrier permeability. These findings confirmed that 3′-daidzein sulfonate sodium has a protective effect on mitochondrial functions after cerebral ischemia/reperfusion injury, improves brain energy metabolism, and provides protection against blood-brain barrier damage.

  17. Copolymers of fluorinated polydienes and sulfonated polystyrene

    DOEpatents

    Mays, Jimmy W.; Gido, Samuel P.; Huang, Tianzi; Hong, Kunlun

    2009-11-17

    Copolymers of fluorinated polydienes and sulfonated polystyrene and their use in fuel cell membranes, batteries, breathable chemical-biological protective materials, and templates for sol-gel polymerization.

  18. Epoxy-crosslinked sulfonated poly (phenylene) copolymer proton exchange membranes

    DOEpatents

    Hibbs, Michael; Fujimoto, Cy H.; Norman, Kirsten; Hickner, Michael A.

    2010-10-19

    An epoxy-crosslinked sulfonated poly(phenylene) copolymer composition used as proton exchange membranes, methods of making the same, and their use as proton exchange membranes (PEM) in hydrogen fuel cells, direct methanol fuel cell, in electrode casting solutions and electrodes, and in sulfur dioxide electrolyzers. These improved membranes are tougher, have higher temperature capability, and lower SO.sub.2 crossover rates.

  19. EVALUATION OF PERFLUOROOCTANE SULFONATE IN THE RAT BRAIN

    EPA Science Inventory

    Perfluorooctane Sulfonate (PFOS) is an environmentally persistent chemical that has been detected in humans and wildlife. PFOS is primarily distributed in liver and blood. The current study evaluated the level of PFOS in the adult and neonatal rat brain and determined whether t...

  20. 40 CFR 721.1625 - Alkylbenzene sulfonate, amine salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.1625 Alkylbenzene sulfonate, amine salt. Link to an amendment published at 79 FR 34636, June 18, 2014. (a) Chemical substance and significant new uses subject to reporting. (1) The...

  1. PERFLUOROOCTANE SULFONATE (PFOS) DISRUPTS THE THYROID STATUS IN LABORATORY RODENTS

    EPA Science Inventory

    PERFLUOROOCTANE SULFONATE (PFOS) DISRUPTS THE THYROID STATUS IN LABORATORY RODENTS. C. Lau, J.R. Thibodeaux, R.G. Hanson, B.E. Gray and J.M. Rogers. Reprod. Tox. Div. NHEERL, US EPA, Research Triangle Park, NC.

    PFOS is an environmental contaminant ubiquitously found in h...

  2. Toxicokinetics of perfluorooctane sulfonate in rainbow trout (Oncorhynchus mykiss)

    EPA Science Inventory

    Rainbow trout (Oncorhynchus mykiss) confined to respirometer-metabolism chambers were dosed with perfluorooctane sulfonate (PFOS) by intra-arterial injection and sampled to obtain concentration time-course data for plasma, and either urine or expired water. The data were then an...

  3. Identification of sulfonic acids as efficient ecto-5'-nucleotidase inhibitors.

    PubMed

    Iqbal, Jamshed; Saeed, Aamer; Raza, Rabia; Matin, Abdul; Hameed, Abdul; Furtmann, Norbert; Lecka, Joanna; Sévigny, Jean; Bajorath, Jürgen

    2013-01-01

    Ecto-5'-nucleotidase (CD73) is well known for its implication in cancer. Inhibition of ecto-5'-nucleotidases is thought to provide an attractive approach to cancer therapy. This study identifies sulfonic acid compounds as efficient inhibitors of ecto-5'-nucleotidases. The compounds were tested against recombinant human and rat ecto-5'-nucleotidases. The most potent new sulfonic acid inhibitor 6-amino-4-hydroxynaphthalene-2-sulfonic acid (1) of ecto-5'-nucleotidase had an IC₅₀ of 1.32 ± 0.09 μM for the human and 10.4 ± 3.3 μM for the rat enzyme. Generally, all compounds were more active against the human enzyme. Plausible binding mode models were developed for this new class of inhibitors. Furthermore, several sulfonic acid inhibitors were efficient cytotoxic agents when tested on H157 cancer cell lines. Hence, new ecto-5'-nucleotidases inhibitors displayed significant potential for further development as compounds for anti-cancer therapy.

  4. Oxidation Potentials of Functionalized Sulfone Solvents for High-Voltage Li-Ion Batteries: A Computational Study

    SciTech Connect

    Shao, Nan; Sun, Xiao-Guang; Dai, Sheng; Jiang, Deen

    2012-01-01

    New electrolytes with large electrochemical windows are needed to meet the challenge for high-voltage Li-ion batteries. Sulfone as an electrolyte solvent boasts of high oxidation potentials. Here we examine the effect of multiple functionalization on sulfone's oxidation potential. We compute oxidation potentials for a series of sulfone-based molecules functionalized with fluorine, cyano, ester, and carbonate groups by using a quantum chemistry method within a continuum solvation model. We find that multifunctionalization is a key to achieving high oxidation potentials. This can be realized through either a fluorether group on a sulfone molecule or sulfonyl fluoride with a cyano or ester group.

  5. Pneumocystis carinii mutations are associated with duration of sulfa or sulfone prophylaxis exposure in AIDS patients.

    PubMed

    Kazanjian, P; Armstrong, W; Hossler, P A; Burman, W; Richardson, J; Lee, C H; Crane, L; Katz, J; Meshnick, S R

    2000-08-01

    This study was conducted to determine whether Pneumocystis carinii dyhydropteroate synthase (DHPS) gene mutations in AIDS patients with P. carinii pneumonia (PCP) are affected by duration of sulfa or sulfone prophylaxis and influence response to sulfa or sulfone therapy. The P. carinii DHPS genes from 97 AIDS patients with PCP between 1991 and 1999 from 4 medical centers were amplified, using polymerase chain reaction (PCR), and sequenced. Mutations were observed in 76% of isolates from patients exposed to sulfa or sulfone prophylaxis compared with 23% of isolates from patients not exposed (P=.001). Duration of prophylaxis increased the risk of mutations (relative risk [RR] for each exposure month, 1.06; P=.02). Twenty-eight percent of patients with mutations failed sulfa or sulfone treatment; mutations increased the risk of sulfa or sulfone treatment failure (RR, 2.1; P=0.01). Thus, an increased duration of sulfa or sulfone prophylaxis increases the chance of developing a P. carinii mutation. The majority of patients with mutations respond to sulfa or sulfone therapy.

  6. Inactivation of the RTEM beta-lactamase from Escherichia coli. Interaction of penam sulfones with enzyme.

    PubMed

    Fisher, J; Charnas, R L; Bradley, S M; Knowles, J R

    1981-05-12

    The characteristics of the reaction of a number of mechanism-based inactivators of the RTEM beta-lactamase have suggested that a common mechanistic pathway may be followed by many of these compounds. These ideas have been tested by the synthesis and evaluation of some penam sulfones as beta-lactamase inactivators. The sulfones of poor beta-lactamase substrates are, as predicted, potent inactivators of the enzyme. A unique serin residue (Ser-70) is labeled by quinacillin sulfone, and it is likely that this serine acts nucleophilically in the normal hydrolytic reaction of the beta-lactamase to form an acyl-enzyme intermediate.

  7. Isolation of a novel mutant strain of Saccharomyces cerevisiae by an ethyl methane sulfonate-induced mutagenesis approach as a high producer of bioethanol.

    PubMed

    Mobini-Dehkordi, Mohsen; Nahvi, Iraj; Zarkesh-Esfahani, Hamid; Ghaedi, Kamran; Tavassoli, Manoochehr; Akada, Rinji

    2008-04-01

    In order to obtain mutant strains showing higher bioethanol production than wild-type strains, a commercial Saccharomyces cerevisiae type was subjected to mutagenesis using ethyl methane sulfonate (EMS). After adding EMS to a shaken yeast suspension, the viability of yeast cells was assessed by diluted sample inoculation to solid yeast-extract peptone glucose (YEPG) medium at 15-min intervals. At 45 min, the viability of yeast cells was estimated to be about 40%. Mutagenized cells were recovered from YEPG broth after incubation at 30 degrees C for 18 h. After this period, EMS-treated yeast cells were grown on solid aerobic low-peptone (ALP) medium containing 2-12% (v/v) ethanol. All plates were incubated at 30 degrees C for 2-6 d in order to form colonies. The mutant strains that tolerated high concentrations of ethanol were selected for bioethanol production in microfuge tubes containing fermentation medium. Formation of bioethanol in small tubes was detected by the distillation-colorimetric method. In addition, trehalose content and invertase activity were determined in each mutant strain. Among many isolated mutant strains, there were six isolated colonies that grew on ALP medium supplemented with 10% (v/v) ethanol and one of them produced bioethanol 17.3% more than the wild type.

  8. Chlorine resistant desalination membranes based on directly sulfonated poly(arylene ether sulfone) copolymers

    DOEpatents

    McGrath, James E [Blacksburg, VA; Park, Ho Bum [Austin, TX; Freeman, Benny D [Austin, TX

    2011-10-04

    The present invention provides a membrane, kit, and method of making a hydrophilic-hydrophobic random copolymer membrane. The hydrophilic-hydrophobic random copolymer membrane includes a hydrophilic-hydrophobic random copolymer. The hydrophilic-hydrophobic random copolymer includes one or more hydrophilic monomers having a sulfonated polyarylsulfone monomer and a second monomer and one or more hydrophobic monomers having a non-sulfonated third monomer and a fourth monomer. The sulfonated polyarylsulfone monomer introduces a sulfonate into the hydrophilic-hydrophobic random copolymer prior to polymerization.

  9. Clinical utility of patiromer, sodium zirconium cyclosilicate, and sodium polystyrene sulfonate for the treatment of hyperkalemia: an evidence-based review

    PubMed Central

    Beccari, Mario V; Meaney, Calvin J

    2017-01-01

    Introduction Hyperkalemia is a serious medical condition that often manifests in patients with chronic kidney disease and heart failure. Renin–angiotensin–aldosterone system inhibitors are known to improve outcomes in these disease states but can also cause drug-induced hyperkalemia. New therapeutic options exist for managing hyperkalemia in these patients which warrant evidence-based evaluation. Aim The objective of this article was to review the efficacy and safety evidence for patiromer, sodium zirconium cyclosilicate (ZS9), and sodium polystyrene sulfonate (SPS) for the treatment of hyperkalemia. Evidence review Current treatment options to enhance potassium excretion are SPS and loop diuretics, which are complicated by ambiguous efficacy and known toxicities. Patiromer and ZS9 are new agents designed to address this treatment gap. Both unabsorbable compounds bind potassium in the gastrointestinal (GI) tract to facilitate fecal excretion. The capacity to bind other medications in the GI tract infers high drug–drug interaction potential, which has been demonstrated with patiromer but not yet investigated with ZS9 or SPS. Phase II and III clinical trials of patiromer and ZS9 demonstrated clear evidence of a dose-dependent potassium-lowering effect and the ability to initiate, maintain, or titrate renin–angiotensin–aldosterone system inhibitors. There is limited evidence base for SPS: two small clinical trials indicated potassium reduction in chronic hyperkalemia. All agents may cause adverse GI effects, although they are less frequent with ZS9. Concerns remain for SPS to cause rare GI damage. Electrolyte abnormalities occurred with patiromer and SPS, whereas urinary tract infections, edema, and corrected QT-interval prolongations were reported with ZS9. Conclusion Patiromer and ZS9 have improved upon the age-old standard SPS for the treatment of hyperkalemia. Additional research should focus on drug–drug interactions in patients on multiple

  10. Morphology and Proton Transport in Sulfonated Block Copolymer and Mesoporous Polymer Electrolyte Membranes

    NASA Astrophysics Data System (ADS)

    Chen, Chelsea; Wong, David; Beers, Keith; Balsara, Nitash

    2013-03-01

    In an effort to understand the fundamentals of proton transport in polymer electrolyte membranes (PEMs), we have developed a series of poly(styrene-b-ethylene-b-styrene) (SES) membranes. The SES membranes were subsequently sulfonated to yield proton conducting S-SES membranes. We examine the effects of sulfonation level, temperature and thermal history on the morphology of S-SES membranes in both dry and hydrated states. The effects of these parameters on water uptake and proton transport characteristics of the membranes are also examined. Furthermore, building upon the strategy we deployed in sulfonating the SES membranes, we fabricated mesoporous S-SES membranes, with pores lined up with the proton conducting channels. These membranes have three distinct phases: structural block, proton-conducting block, and void. We examine the effects of pore size, domain structure and sulfonation level on water uptake and proton conductivity of the mesoporous PEMs at different temperatures. This work is funded by Department of Energy.

  11. Synthesis of new sulfonylamido-penicillanic acid sulfones inhibitors of beta-lactamases.

    PubMed

    Vanwetswinkel, S; Fastrez, J; Marchand-Brynaert, J

    1994-09-01

    Three new sulfonylamido-penicillanic acid sulfones have been prepared by reaction of 6-aminopenicillanic esters with the monoester or monoamide derivatives obtained in nucleophilic substitution reactions by alcohol or aniline on the carboxyl chloride function of sulfoacetic dichloride followed by oxidation. These penicillin sulfones are converted to beta-lactamases suicide inhibitors by removal of the C3 ester protecting group. This synthetic strategy can give access to sulfonamidopenam sulfones bearing a variety of 6-amino side chain. These inhibitors inactivate the RTEM beta-lactamase rapidly. The kinetics of inactivation are consistent with the partitioning of an acylenzyme intermediate between two main pathways: regeneration of free enzyme and irreversible inactivation, little transient inactivation is observed. A slow inhibition by the product of enzymatic hydrolysis of the sulfones is also observed.

  12. Electric current-producing device having sulfone-based electrolyte

    DOEpatents

    Angell, Charles Austen; Sun, Xiao-Guang

    2010-11-16

    Electrolytic solvents and applications of such solvents including electric current-producing devices. For example, a solvent can include a sulfone compound of R1--SO2--R2, with R1 being an alkyl group and R2 a partially oxygenated alkyl group, to exhibit high chemical and thermal stability and high oxidation resistance. For another example, a battery can include, between an anode and a cathode, an electrolyte which includes ionic electrolyte salts and a non-aqueous electrolyte solvent which includes a non-symmetrical, non-cyclic sulfone. The sulfone has a formula of R1--SO2--R2, wherein R1 is a linear or branched alkyl or partially or fully fluorinated linear or branched alkyl group having 1 to 7 carbon atoms, and R2 is a linear or branched or partially or fully fluorinated linear or branched oxygen containing alkyl group having 1 to 7 carbon atoms. The electrolyte can include an electrolyte co-solvent and an electrolyte additive for protective layer formation.

  13. Radiation-induced crosslinking of poly(styrene-butadiene-styrene) block copolymers and their sulfonation

    NASA Astrophysics Data System (ADS)

    Lee, Sun-Young; Song, Ju-Myung; Sohn, Joon-Yong; Shul, Yong-Gun; Shin, Junhwa

    2013-12-01

    Several crosslinked poly(styrene-butadiene-styrene) (c-SBS) block copolymer films were prepared using a gamma ray or electron beam with various irradiation doses and the prepared c-SBS film was then subjected to sulfonation using a chlorosulfonic acid (CSA) solution to introduce a sulfonic acid group. To estimate the degree of crosslinking, the gel fractions and FT-IR spectra of the c-SBS films were used and the results indicate that the degree of crosslinking is increased with an increase in the radiation dose. The surface morphology and mechanical property of the c-SBS films were observed using SEM and UTM instruments, respectively. The sulfonated c-SBS films were investigated by measuring the ion exchange capacity (IEC) and by observing the cross-sectional distribution patterns of sulfonic acid group using an SEM-EDX instrument. The IEC and SEM-EDX studies indicate that the sulfonated c-SBS membranes can be successfully prepared through the radiation crosslinking of the SBS film and the subsequent sulfonation with a diluted CSA solution.

  14. Toxicological properties and risk assessment of the anionic surfactants category: Alkyl sulfates, primary alkane sulfonates, and α-olefin sulfonates.

    PubMed

    Wibbertmann, Axel; Mangelsdorf, Inge; Gamon, Konrad; Sedlak, Richard

    2011-07-01

    The category of the anionic surfactants (ANS) consisting of 46 alkyl sulfates, 6 primary alkane sulfonates, and 9 α-olefin sulfonates has been assessed under the high production volume (HPV) chemicals program of the Organisation for Economic Cooperation and Development (OECD) in 2007. In this review the toxicological properties of these chemicals are summarized. The chemicals of this category are used predominantly in detergents, household cleaning products, and cosmetics. These chemicals show low acute and repeat dose toxicity. There was no evidence of genetic or reproductive toxicity, or carcinogenicity. There also was no indication for sensitizing properties. Skin and eye irritating effects in consumers are not to be expected. For consumers, the calculated body burden is about 10,000 times lower than the lowest NOAEL value in experimental animals, so that adverse effects caused by substances of the ANS category can be excluded.

  15. Effect of additives on the performance and morphology of sulfonated copoly (phthalazinone biphenyl ether sulfone) composite nanofiltration membranes☆

    NASA Astrophysics Data System (ADS)

    Guan, Shanshan; Zhang, Shouhai; Liu, Peng; Zhang, Guozhen; Jian, Xigao

    2014-03-01

    Sulfonated copoly (phthalazinone biphenyl ether sulfone) (SPPBES) composite nanofiltration membranes were fabricated by adding low molecular weight additives into SPPBES coating solutions during a dip coating process. Three selected additives: glycol, glycerol and hydroquinone were used in this work. The effect of additives on the membrane performance was studied and discussed in terms of rejection and permeation flux. Among all the composite membranes, the membrane prepared with glycol as an additive achieved the highest Na2SO4 rejection, and the membrane fabricated with glycerol as an additive exhibited the highest flux. The salts rejection of SPPBES composite membranes increased in the following order MgCl2 < NaCl ≤ MgSO4 < Na2SO4. The morphologies of the SPPBES composite membranes were characterized by SEM, it was found that the membrane prepared with hydroquinone showed a rough membrane surface. Composite membrane fabricated with glycol or glycerol as the additive showed very good chemical stability.

  16. Amperometric urea biosensors based on sulfonated graphene/polyaniline nanocomposite

    PubMed Central

    Das, Gautam; Yoon, Hyon Hee

    2015-01-01

    An electrochemical biosensor based on sulfonated graphene/polyaniline nanocomposite was developed for urea analysis. Oxidative polymerization of aniline in the presence of sulfonated graphene oxide was carried out by electrochemical methods in an aqueous environment. The structural properties of the nanocomposite were characterized by Fourier-transform infrared, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy techniques. The urease enzyme-immobilized sulfonated graphene/polyaniline nanocomposite film showed impressive performance in the electroanalytical detection of urea with a detection limit of 0.050 mM and a sensitivity of 0.85 (μA · cm−2·mM−1. The biosensor achieved a broad linear range of detection (0.12–12.3 mM) with a notable response time of approximately 5 seconds. Moreover, the fabricated biosensor retained 81% of its initial activity (based on sensitivity) after 15 days of storage at 4°C. The ease of fabrication coupled with the low cost and good electrochemical performance of this system holds potential for the development of solid-state biosensors for urea detection. PMID:26346240

  17. Amperometric urea biosensors based on sulfonated graphene/polyaniline nanocomposite.

    PubMed

    Das, Gautam; Yoon, Hyon Hee

    2015-01-01

    An electrochemical biosensor based on sulfonated graphene/polyaniline nanocomposite was developed for urea analysis. Oxidative polymerization of aniline in the presence of sulfonated graphene oxide was carried out by electrochemical methods in an aqueous environment. The structural properties of the nanocomposite were characterized by Fourier-transform infrared, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy techniques. The urease enzyme-immobilized sulfonated graphene/polyaniline nanocomposite film showed impressive performance in the electroanalytical detection of urea with a detection limit of 0.050 mM and a sensitivity of 0.85 (μA · cm(-2)·mM(-1). The biosensor achieved a broad linear range of detection (0.12-12.3 mM) with a notable response time of approximately 5 seconds. Moreover, the fabricated biosensor retained 81% of its initial activity (based on sensitivity) after 15 days of storage at 4°C. The ease of fabrication coupled with the low cost and good electrochemical performance of this system holds potential for the development of solid-state biosensors for urea detection.

  18. Susceptibility of Candida albicans to new synthetic sulfone derivatives.

    PubMed

    Staniszewska, Monika; Bondaryk, Małgorzata; Ochal, Zbigniew

    2015-02-01

    The influence of halogenated methyl sulfones, i.e. bromodichloromethyl-4-chloro-3-nitrophenyl sulfone (named halogenated methyl sulfone 1), dichloromethyl-4-chloro-3-nitrophenyl sulfone (halogenated methyl sulfone 2), and chlorodibromomethyl-4-hydrazino-3-nitrophenyl sulfone (halogenated methyl sulfone 3), on cell growth inhibition, aspartic protease gene (SAP4-6) expression, adhesion to epithelium, and filamentation was investigated. Antifungal susceptibility of the halogenated methyl sulfones was determined with the M27-A3 protocol in the range of 16-0.0313 µg/mL. Adherence to Caco-2 cells was performed in 24-well plates; relative quantification was normalized against ACT1 in cells after 18 h of growth in YEPD and on Caco-2 cells. SAP4-6 expression was analyzed using RT-PCR. Structure-activity relationship studies suggested that halogenated methyl sulfone 1 containing bromodichloromethyl or dichloromethyl function at C-4 (halogenated methyl sulfone 2) of the phenyl ring showed the best activity (100% cell inhibition at 0.5 µg/mL), while hydrazine at C-1 (halogenated methyl sulfone 3) reduced the sulfone potential (100% = 4 µg/mL). SAP4-6 were up- or down-regulated depending on the strains' genetic background and the substitutions on the phenyl ring. Halogenated methyl sulfone 2 repressed germination and affected adherence to epithelium (P ≤ 0.05). The tested halogenated methyl sulfones interfered with the adhesion of Candida albicans cells to the epithelial tissues, without affecting their viability after 90 min of incubation. The mode of action of the halogenated methyl sulfones was attributed to the reduced virulence of C. albicans. SAP5 and SAP6 contribute to halogenated methyl sulfones resistance. Thus, halogenated methyl sulfones can inhibit biofilm formation due to their interference with adherence and with the yeast-to-hyphae transition.

  19. Composite plasma polymerized sulfonated polystyrene membrane for PEMFC

    SciTech Connect

    Nath, Bhabesh Kumar; Khan, Aziz; Chutia, Joyanti

    2015-10-15

    Highlights: • Methyl methane sulfonate (MMS) is used as the sulfonating agent. • The proton conductivity of the membrane is found to be 0.141 S cm{sup −1}. • Power density of fuel cell with styrene/MMS membrane is 0.5 W cm{sup −2}. • The membrane exhibits thermal stability up to 140 °C. - Abstract: This work presents the introduction of an organic compound methyl methane sulfonate (MMS) for the first time in fabrication of polystyrene based proton exchange membrane (PEM) by plasma polymerization process. The membrane is fabricated by co-polymerizing styrene and MMS in capacitively coupled continuous RF plasma. The chemical composition of the plasma polymerized polymer membrane is investigated using Fourier Transform Infrared Spectroscopy which reveals the formation of composite structure of styrene and MMS. The surface morphology studied using AFM and SEM depicts the effect of higher partial pressure of MMS on surface topography of the membrane. The proton transport property of the membrane studied using electrochemical impedance spectroscopy shows the achievement of maximum proton conductivity of 0.141 S cm{sup −1} which is comparable to Nafion 117 membrane. Fuel cell performance test of the synthesized membrane shows a maximum power density of 500 mW cm{sup −2} and current density of 0.62 A cm{sup −2} at 0.6 V.

  20. Simulation study of sulfonate cluster swelling in ionomers

    NASA Astrophysics Data System (ADS)

    Allahyarov, Elshad; Taylor, Philip L.; Löwen, Hartmut

    2009-12-01

    We have performed simulations to study how increasing humidity affects the structure of Nafion-like ionomers under conditions of low sulfonate concentration and low humidity. At the onset of membrane hydration, the clusters split into smaller parts. These subsequently swell, but then maintain constant the number of sulfonates per cluster. We find that the distribution of water in low-sulfonate membranes depends strongly on the sulfonate concentration. For a relatively low sulfonate concentration, nearly all the side-chain terminal groups are within cluster formations, and the average water loading per cluster matches the water content of membrane. However, for a relatively higher sulfonate concentration the water-to-sulfonate ratio becomes nonuniform. The clusters become wetter, while the intercluster bridges become drier. We note the formation of unusual shells of water-rich material that surround the sulfonate clusters.

  1. Ion Exchange Formation via Sulfonated Bicomponent Nonwovens

    NASA Astrophysics Data System (ADS)

    Stoughton, Hannah L.

    For many years ion exchange resins were used to: remove heavy metals from water, recover materials from wastewater, and eliminate harmful gases from the air. While use of these resin beads dominates the ion exchange industry, the beads have limitations that should be considered when decisions are made to employ them. For instance, officials must balance the inherent zero sum surface area and porosity of the materials. This series of studies investigates the use of bicomponent nonwovens as a base substrate for producing high surface area ion exchange materials for the removal of heavy metal ions. Functionalized materials were produced in a two-step process: (1) PET/PE spunbond bicomponent fibers were fractured completely, producing the high surface area nonwoven to be used as the base ion exchange material, and (2) the conditions for functionalizing the PET fibers of the nonwoven webs were investigated where an epoxy containing monomer was grafted to the surface followed by sulfonation of the monomer. The functionalization reactions of the PET fibers were monitored based on: weight gain, FTIR, TOF-SIMS, and SEM. Ion exchange properties were evaluated using titration and copper ion removal capacity from test solutions. The relationship between web structure and removal efficiency of the metal ions was defined through a comparison of the bicomponent and homocomponent nonwovens for copper ion removal efficiency. The investigation revealed that utilizing the high surface area, fractured bicomponent nonwoven ion exchange materials with capacities comparable to commercially available ion exchange resins could be produced.

  2. Fibronectin fibrillogenesis on sulfonated polystyrene surfaces.

    PubMed

    Pernodet, Nadine; Rafailovich, Miriam; Sokolov, Jonathan; Xu, D; Yang, Nan-Loh; McLeod, Kenneth

    2003-03-15

    Extracellular matrix (ECM) protein adsorption and organization serves as a critical first step in the development and organization of tissues. Advances in tissue engineering, therefore, will depend on the ability to control the rate and pattern of ECM formation. Fibronectin is a prominent component of the ECM, which undergoes fibrillogenesis in the presence of cells. Using sulfonated polysyrene surfaces, we showed that fibronectin undergoes a transition from monolayer to multilayer adsorption at calculated surface charge densities above 0.03 Coulombs (C)/m(2). At charge densities above approximately 0.08 C/m(2), distinct fibronectin fibrillar networks are observed to form with a fibril morphology similar to those observed to form in situ on cell surfaces. This self-organization process is time dependent, with the fibrils achieving dimensions of 30-40 microm in length and 1 microm in height after 72 h of incubation. We suggest that the polarization of charge domains on the polyampholytic fibronectin molecules near high charge density surfaces is sufficient to initiate the multilayer adsorption and the organization of these fibrillar structures. These results suggest that the nonlinear dependence of adsorption on surface charge density may play an important role in the self-organization of many matrix components.

  3. Precipitation of alkylbenzene sulfonates with metal ions

    SciTech Connect

    Peacock, J.M.; Matijevic, E.

    1980-10-01

    The precipitation domains of P-(1-methylnonyl)benzene sulfonate ions with Li/sup +/, Na/sup +/, K/sup +/, Ca/sup 2 +/, Mg/sup 2 +/, Al/sup 3 +/, and La/sup 3 +/ and of Ca/sup 2 +/-P-(hexyloctyl)benzene sulfonate have been determined at constant pH and 25 C. The linear solubility boundaries reverse their slope at the critical micellar concentration of the surfactant. A semiquantitative interpretation of the data is offered. The properties of the solids formed also are described. 18 references.

  4. An 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)-immobilized electrode for the simultaneous detection of dopamine and uric acid in the presence of ascorbic acid.

    PubMed

    Chih, Yi-Kai; Yang, Ming-Chang

    2013-06-01

    An 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS)-immobilized carbon nanotube (CNT) electrode was used to simultaneously detect dopamine (DA) and uric acid (UA) in the presence of ascorbic acid (AA) with differential pulse voltammetry. When ABTS was immobilized onto the CNT electrode in the presence of DA, UA and 100 μM AA, the sensitivity to DA increased from 0.600 (±0.013) to 1.334 (±0.010) μA/μM in the concentration ranges of 0.90-10 μM and 1.87-20 μM, respectively, and the sensitivity to UA increased from 0.030 (±0.005) to 0.078 (±0.006) μA/μM in the concentration ranges of 2.16-240 μM and 3.07-400 μM, respectively. These findings demonstrate that the ABTS-immobilized CNT electrode attained a higher sensitivity to UA and also a wider linear range of concentrations.

  5. 40 CFR 721.1625 - Alkylbenzene sulfonate, amine salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkylbenzene sulfonate, amine salt... Substances § 721.1625 Alkylbenzene sulfonate, amine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkylbenzene sulfonate,...

  6. 40 CFR 721.10035 - Alkylbenzene sulfonate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkylbenzene sulfonate (generic). 721... Substances § 721.10035 Alkylbenzene sulfonate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkylbenzene sulfonate...

  7. 40 CFR 721.1625 - Alkylbenzene sulfonate, amine salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkylbenzene sulfonate, amine salt... Substances § 721.1625 Alkylbenzene sulfonate, amine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkylbenzene sulfonate,...

  8. 40 CFR 721.10035 - Alkylbenzene sulfonate (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkylbenzene sulfonate (generic). 721... Substances § 721.10035 Alkylbenzene sulfonate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkylbenzene sulfonate...

  9. 40 CFR 721.10672 - Sodium olefin sulfonate derivative (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Sodium olefin sulfonate derivative... Specific Chemical Substances § 721.10672 Sodium olefin sulfonate derivative (generic). (a) Chemical... as sodium olefin sulfonate derivative (PMNs P-09-447 and P-09-448) are subject to reporting...

  10. Adsorption of cyanophage AS-1 to unicellular cyanobacteria and isolation of receptor material from Anacystis nidulans.

    PubMed Central

    Samimi, B; Drews, G

    1978-01-01

    Cells of unicellular cyanobacteria of typological group Ia, containing approximately 50 mol% guanine + cytosine (G+C) in their DNA (R. Y. Stanier, R. Kunisawa, M. Mandel, and G. Cohen-Bazire, Bacteriol. Rev. 35:171-205, 1971), were susceptible to infection by the cyanophage AS-1. Cyanobacteria of the same typological group, containing approximately 65 mol% G+C in their DNA, did not adsorb the cyanophage AS-1 or adsorbed it at a low rate. AS-1 was not propagated by any of the investigated strains with a high G+C content in their DNA. However, cells of strains 6907 and 6911 were lysed by cyanophage AS-1. A comparison of the host range of this phage with the lipopolysaccharide composition of host and non-host cell walls suggests that lipopolysaccharides are involved in the adsorption process. About 8 microgram of lipopolysaccharide per ml from host strains inactivated 50% of the particles of a solution containing 100 PFU/ml after 60 min of incubation at 30 degrees C. Material with receptor activity was extracted from the host strain Anacystis nidulans KM. The extract was purified of glycolipids and pigments, and a fraction showing receptor activity was isolated. This fraction contained three polypeptides of molecular weights between 54,000 and 64,000. Heat and protease treatment of whole cells and of isolated receptor material decreased the receptor activity. The fluorescence intensity of A. nidulans cells labeled with 1-anilino-8-naphthalene sulfonate was increased when AS-1 was adsorbed to these cells. The participation of lipopolysaccharides and proteins in the formation of the receptor complex is discussed. Images PMID:413935

  11. Radiation synthesis of eco-friendly water reducing sulfonated starch/acrylic acid hydrogel designed for cement industry

    NASA Astrophysics Data System (ADS)

    Abd El-Rehim, H. A.; Hegazy, El-Sayed A.; Diaa, D. A.

    2013-04-01

    Starch was treated with chlorosulfonic acid to obtain sulfonated starch. Acrylic acid/sulfonated starch semi-interpenetrated network IPN of different compositions was prepared using ionizing radiation. Swelling of prepared IPNs at different environmental conditions was studied. The possible use of sulfonated starch/acrylic acid IPN as a water-retarding agent in the cement industry was investigated. ζ-potential measurements were used to determine the stability of the colloidal cement—SS/AA and cement -poly-naphthalene sulfonic acid (SNF) water retarding mixtures. Sulfonated starch/acrylic acid water-retarding property was influenced by hydrogel concentration and composition. Sulfonated starch/acrylic acid IPN admixture has a great effect on the cement initial setting time. Using 2% of SS/AA or SNF resulted in an increase in initial setting time by 2 and 1 h respectively, if compared with native cement initial setting time. The results showed that the synthetic commercial super-plasticizers could be replaced by an eco-friendly water-retarding sulfonated starch/acrylic acid IPN in the cement industry.

  12. Nitric Acid Dehydration Using Perfluoro Carboxylate and Mixed Sulfonate/Carboxylate Membranes

    SciTech Connect

    Ames, Richard L.

    2004-09-01

    Perfluoro ionomer membranes are tetrafluoro ethylene-based materials with microheterogeneous structures consisting of a hydrophobic polymer backbone and a hydrophilic side-chain cluster region. Due to the ionomer cluster morphology, these films exhibit unique transport properties. Recent investigations with perfluoro sulfonate and perfluoro sulfonate/carboxylate composite polymers have demonstrated their value in the dehydration of nitric acid and they show potential as an alternative to conventional, energy intensive unit operations in the concentration of acid feeds. As a result, investigations were conducted to determine the feasibility of using pure perfluoro carboxylate and mixed perfluoro sulfonate/carboxylate films for the dehydration of nitric acid because of the speculation of improved water selectivity of the carboxylate pendant chain. During the first phase of these investigations the effort was focused on generating a thin, solution cast perfluoro carboxylate ionomer film, to evaluate the general, chemical and physical characteristics of the polymer, and to assess the material's aqueous transport performance (flux and nitrate separation efficiencies) in pervaporation and high-pressure environments. Results demonstrated that generating robust solution-cast films was difficult yet a number of membranes survived high trans-membrane pressures up to 700 psig. General characterization of the solution cast product showed reduced ion exchange capacities when compared with thicker, ''as received'' perfluoro carboxylate and similar sulfonate films. Small angle x-ray scattering analysis results suggested that the solution cast carboxylate films contained a small fraction of sulfonate terminated side-chains. Aqueous transport experimentation showed that permeate fluxes for both pure water and nitric acid were approximately two orders of magnitude smaller for the carboxylate solution cast membranes when compared to their sulfonate counterparts of similar thickness

  13. Randomized Clinical Trial of Sodium Polystyrene Sulfonate for the Treatment of Mild Hyperkalemia in CKD

    PubMed Central

    Lepage, Laurence; Dufour, Anne-Claude; Doiron, Jessica; Handfield, Katia; Desforges, Katherine; Bell, Robert; Vallée, Michel; Savoie, Michel; Perreault, Sylvie; Laurin, Louis-Philippe; Pichette, Vincent

    2015-01-01

    Background and objectives Hyperkalemia affects up to 10% of patients with CKD. Sodium polystyrene sulfonate has long been prescribed for this condition, although evidence is lacking on its efficacy for the treatment of mild hyperkalemia over several days. This study aimed to evaluate the efficacy of sodium polystyrene sulfonate in the treatment of mild hyperkalemia. Design, setting, participants, & measurements In total, 33 outpatients with CKD and mild hyperkalemia (5.0–5.9 mEq/L) in a single teaching hospital were included in this double–blind randomized clinical trial. We randomly assigned these patients to receive either placebo or sodium polystyrene sulfonate of 30 g orally one time per day for 7 days. The primary outcome was the comparison between study groups of the mean difference of serum potassium levels between the day after the last dose of treatment and baseline. Results The mean duration of treatment was 6.9 days. Sodium polystyrene sulfonate was superior to placebo in the reduction of serum potassium levels (mean difference between groups, −1.04 mEq/L; 95% confidence interval, −1.37 to −0.71). A higher proportion of patients in the sodium polystyrene sulfonate group attained normokalemia at the end of their treatment compared with those in the placebo group, but the difference did not reach statistical significance (73% versus 38%; P=0.07). There was a trend toward higher rates of electrolytic disturbances and an increase in gastrointestinal side effects in the group receiving sodium polystyrene sulfonate. Conclusions Sodium polystyrene sulfonate was superior to placebo in reducing serum potassium over 7 days in patients with mild hyperkalemia and CKD. PMID:26576619

  14. Room temperature synthesis of biodiesel using sulfonated ...

    EPA Pesticide Factsheets

    Sulfonation of graphitic carbon nitride (g-CN) affords a polar and strongly acidic catalyst, Sg-CN, which displays unprecedented reactivity and selectivity in biodiesel synthesis and esterification reactions at room temperature. Prepared for submission to Royal Society of Chemistry (RSC) journal, Green Chemistry as a communication.

  15. Color reduction of sulfonated eucalyptus kraft lignin.

    PubMed

    Zhang, Hui; Bai, Youcan; Zhou, Wanpeng; Chen, Fangeng

    2017-04-01

    Several eucalyptus lignins named as HSL, SML and BSL were prepared by high temperature sulfonation, sulfomethylation, butane sultone sulfonation respectively. The color properties of samples were investigated. Under optimized conditions the sulfonic group (SO3H) content of HSL, SML and BSL reached 1.52, 1.60 and 1.58mmol/g, respectively. Samples were characterized by UV-vis spectroscopy, FTIR spectroscopy, (1)H NMR spectroscopy, GPC and brightness test, respectively. The results revealed that BSL performed a higher molecular weight and lighter color due to the phenolic hydroxyl blocking by 1,4-butane sultone (1,4-BS). The color reduction of sodium borohydride treated BSL (labeled as SBSL) was further enhanced and the brightness value was improved by 76.1% compared with the darkest HSL. SBSL process was much better than HSL and SML process. Hydroxyl blocking effect of 1,4-BS and reducibility of sodium borohydride played important roles in the color reduction of sulfonated eucalyptus kraft lignin.

  16. 21 CFR 573.600 - Lignin sulfonates.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food... accordance with the following prescribed conditions: (a) For the purpose of this section, the food additive... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Lignin sulfonates. 573.600 Section 573.600...

  17. 21 CFR 573.600 - Lignin sulfonates.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food... accordance with the following prescribed conditions: (a) For the purpose of this section, the food additive... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Lignin sulfonates. 573.600 Section 573.600...

  18. 21 CFR 573.600 - Lignin sulfonates.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food... accordance with the following prescribed conditions: (a) For the purpose of this section, the food additive... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Lignin sulfonates. 573.600 Section 573.600...

  19. High speed and reproducible analysis of nitrosamines by capillary electrophoresis with a sulfonated capillary.

    PubMed

    Taga, Atsushi; Nishi, Tomoko; Honda, Yoshitaka; Sato, Atsushi; Terashima, Hiroyuki; Suzuki, Kentaro; Kodama, Shuji; Boki, Keito

    2007-01-01

    Recently environmental control is regarded as important for good human health conditions, and toxic substances, including carcinogens and endocrine disruptors should be eliminated from our living environment. Hence easy quantitative methods are expected for a high level of environmental control. Our previous paper describes an easy quantitative analysis of nitrosamines (NAs) by capillary electrophoresis with an untreated fused silica capillary installed in an ordinary apparatus. In this paper, utilizing a novel type capillary column having sulfonated inner wall was investigated for improvements of separation performance and reproducibility. A sulfonated capillary causes fast and stabile electroosmotic flow because its inner wall is strongly negative charged. On a performance comparison of a sulfonated capillary with an untreated fused silica, analysis time reduction of c.a. forty percent was achieved, and relative standard deviations of migration times and peak responses were less than one third. In addition sample concentrations giving detection and quantitation limits were also reduced to a half.

  20. Hydrocarbon and partially fluorinated sulfonated copolymer blends as functional membranes for proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Arnett, Natalie Y.; Harrison, William L.; Badami, Anand S.; Roy, Abhishek; Lane, Ozma; Cromer, Frank; Dong, Limin; McGrath, James E.

    Polymer blending is recognized as a valuable technique used to modify and improve the mechanical, thermal, and surface properties of two different polymers or copolymers. This paper investigated the solution properties and membrane properties of a biphenol-based disulfonated poly (arylene ether sulfone) random copolymer (BPS-35) with hexafluoroisopropylidene bisphenol based sulfonated poly (arylene ether sulfone) copolymers (6FSH) and an unsulfonated biphenol-based poly (arylene ether sulfone)s. The development of blended membranes with desirable surface characteristics, reduced water swelling and similar proton conductivity is presented. Polymer blends were prepared both in the sodium salt and acid forms from dimethylacetamide (DMAc). Water uptake, specific conductivity, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and contact angles were used to characterize the blended films. Surface enrichment of the fluorinated component is illustrated by an significant increase in the water-surface contact angle was observed when 10 wt.% 6FBPA-00 (106°) was added to BPS 35 (80°). Water weight gain was reduced by a factor of 2.

  1. Sulfonated and sulfoacylated poly(styrene-divinylbenzene) copolymers as packing materials for cation chromatography.

    PubMed

    Pirogov, Andrey V; Chernova, Marina V; Nemtseva, Dar'ya S; Shpigun, Oleg A

    2003-07-01

    Three different types of cation exchangers were produced from four basic poly(styrene-divinylbenzene) substrates with different properties. Porous PS-DVB resin beads were functionalized by sulfonation and sulfoacylation under various conditions to produce sulfonated resins with exchange capacities of 0.03-1.80 mM g(-1). The matrix with 50% of cross-linking is most suitable for updating by the proposed technique. Sulfuric and chlorosulfonic acids were used as the reagents for sulfonation. The sulfonating conditions, capacities, and the technique of the synthesis are given. The effects of parameters of the sulfonation reaction and the composition of the reactionary mixture on ion-exchange capacity of the sorbents were investigated. Selectivity and efficiency of the separation of some inorganic cations and derivatives of amines and hydrazines on the resins obtained are compared by ion chromatography with conductometric detection. As a result, the sulfoacylated resin was proved more efficient for the separation of these analytes. The resolution of the analytes strongly depends on the degree of functionalization. The best performance about 19,000 plates m(-1) was obtained using the sulfopropionylated beads with an ion-exchange capacity of 0.3 mM g(-1). The prepared sulfoacylated cation exchanger was compared with the commercially available Dionex CS-12 packing material. It was found that the separation of alkaline ions and 1,1-dimethylhydrazine (UDMH) were much better that those for the commercial material.

  2. [New synthesis of the anticoagulant pentasaccharide idraparinux and preparation of its analogues containing sulfonic acid moieties].

    PubMed

    Herczeg, Mihály

    2012-01-01

    Two novel synthetic pathways were elaborated for the preparation of idraparinux, a heparin-related fully O-sulfated, O-methylated anticoagulant pentasaccharide. Both methods based upon a [2+3] block synthesis utilizing the same trisaccharide acceptor which was coupled to either a uronic acid disaccharide donor or its nonoxidized precursor. Two bioisosteric sulfonic acid analogues of idraparinux were also prepared, in which two or three primary sulfate esters were replaced by sodium-sulfonatomethyl moieties. The sulfonic acid groups were formed on a monosaccharide level and the obtained carbohydrate sulfonic acid esters were found to be excellent donors and acceptors in the glycosylation reactions. The disulfonic-acid analogue was prepared in a [2+3] block synthesis by using a trisaccharide disulfonic acid as an acceptor and a glucuronide disaccharide as a donor. For the synthesis of the pentasaccharide trisulfonic acid, a more-efficient approach, which involved elongation of the trisaccharide acceptor with a non-oxidized precursor of the glucuronic acid followed by post-glycosidation oxidation at the tetrasaccharide level and a subsequent [1+4] coupling reaction, was elaborated. In vitro evaluation of the anticoagulant activity of the reference compound idraparinux and the new sulfonic acid derivatives revealed that the disulfonate analogue inhibited the blood-coagulation-proteinase factor Xa with outstanding efficacy; however, the introduction of the third sulfonic acid moiety resulted in a notable decrease in the anti-Xa activity.

  3. Polymer electrolyte membranes from fluorinated polyisoprene-block-sulfonated polystyrene: Membrane structure and transport properties

    SciTech Connect

    Sodeye, Akinbode; Huang, Tianzi; Gido, Samuel; Mays, Jimmy

    2011-01-01

    With a view to optimizing morphology and ultimately properties, membranes have been cast from relatively inexpensive block copolymer ionomers of fluorinated polyisoprene-block-sulfonated polystyrene (FISS) with various sulfonation levels, in both the acid form and the cesium neutralized form. The morphology of these membranes was characterized by transmission electron microscopy and ultra-small angle X-ray scattering, as well as water uptake, proton conductivity and methanol permeability within the temperature range from 20 to 60 C. Random phase separated morphologies were obtained for all samples except the cesium sample with 50 mol% sulfonation. The transport properties increased with increasing degree of sulfonation and temperature for all samples. The acid form samples absorbed more water than the cesium samples with a maximum swelling of 595% recorded at 60 C for the acid sample having 50 mol% sulfonation. Methanol permeability for the latter sample was more than an order of magnitude less than for Nafion 112 but so was the proton conductivity within the plane of the membrane at 20 C. Across the plane of the membrane this sample had half the conductivity of Nafion 112 at 60 C.

  4. Chronic Exposure of Female Mice to an Environmental Level of Perfluorooctane Sulfonate Suppresses Estrogen Synthesis Through Reduced Histone H3K14 Acetylation of the StAR Promoter Leading to Deficits in Follicular Development and Ovulation.

    PubMed

    Feng, Xuejiao; Wang, Xiaoli; Cao, Xinyuan; Xia, Yankai; Zhou, Rong; Chen, Ling

    2015-12-01

    Perfluorooctane sulfonate (PFOS) at a high dose of 10 mg/kg has been reported to affect the neuroendocrine system and exert toxic effects in rodents. The present study examined the influence of chronic exposure to a low-dose of PFOS (0.1 mg/kg/day) on female reproductive endocrine and function. Herein, we show that adult female mice exposed to PFOS by gavage for 4 months (PFOS-mice) exhibited a prolongation of diestrus without signs of toxic effects. The numbers of mature follicles and corpora luteum were significantly reduced in PFOS-mice with increase of atresic follicles. The levels of serum estrogen (E2) and progesterone at proestrus and diestrus were reduced in PFOS-mice. In comparison with controls, PFOS-mice showed a significant decrease in the levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH), and gonadotrophin-releasing hormone, the number of kisspeptin neurons and the level of kiss1 mRNA in anteroventral periventricular nucleus at proestrus but not at diestrus, which could be corrected with the normalization to E2. PFOS-mice did not generate an LH-surge at proestrus, which could be rescued by the application of E2 or kisspeptin-10. Notably, the level of ovarian steroidogenic acute regulatory (StAR) mRNA was decreased in PFOS-mice with the reduction of histone H3K14 acetylation in StAR promoter relative to control mice, whereas the P450scc expression and histone H3K14 acetylation showed no difference between the groups. The present study provides evidence that the chronic exposure to the low-dose of PFOS through selectively reducing histone acetylation of StAR suppresses the biosynthesis of E2 to impair the follicular development and ovulation.

  5. Sulfonated nanoporous colloidal films and membranes

    NASA Astrophysics Data System (ADS)

    Smith, Joanna Jane

    The objective of this thesis is to describe the preparation and investigation of a new class of proton-conducting membrane materials, namely, nanoporous colloidal membranes whose proton conductivity results from the nanopore surface modification with organic molecules carrying acid functionalities. Both the proton transport and ion transport were studied in nanoporous silica colloidal crystals that were surface modified with sulfonic groups. First, the transport of ions was studied through sulfonated silica colloidal films that were supported on platinum electrodes using cyclic voltammetry. The surface of self-assembled nanoporous silica colloidal crystalline films was sulfonated using 1,3-propanesultone. We found that the flux of anions through the sulfonated colloidal films is reduced, while the flux of cations is increased, compared to the unmodified colloidal films. Second, the proton transport in free-standing assemblies of surface-sulfonated silica nanospheres, either randomly packed or self-assembled into a close-packed arrangement, were studied. It was demonstrated that colloidal assemblies prepared using surface-sulfonated silica nanospheres posses proton conductivity that depends on the ordering of the material, temperature and relative humidity. Based on the comparison between the close-packed and disordered assemblies made of the same spheres, we conclude that the increase in structural organization of the self-assembled colloidal materials leads to increased proton conductivity and better water retention. Next free-standing colloidal membranes with a relatively large area and no mechanical defects were prepared by sintering silica colloidal films. The sintered membranes were then surface rehydroxylated, which restores the surface silanol groups, and then can be chemically modified. Finally, sintered self-assembled nanoporous silica colloidal crystals were modified with poly(sulfopropyl-methacrylate) (pSPM) and poly(stryrenesulfonic acid) (pSSA) brushes

  6. Highly branched sulfonated poly(fluorenyl ether ketone sulfone)s membrane for energy efficient vanadium redox flow battery

    NASA Astrophysics Data System (ADS)

    Yin, Bibo; Li, Zhaohua; Dai, Wenjing; Wang, Lei; Yu, Lihong; Xi, Jingyu

    2015-07-01

    A series of highly branched sulfonated poly (fluorenyl ether ketone sulfone)s (HSPAEK) are synthesized by direct polycondensation reactions. The HSPAEK with 8% degree of branching is further investigated as membrane for vanadium redox flow battery (VRFB). The HSPAEK membrane prepared by solution casting method exhibits smooth, dense and tough morphology. It possesses very low VO2+ permeability and high ion selectivity compared to those of Nafion 117 membrane. When applied to VRFB, this novel membrane shows higher coulombic efficiency (CE, 99%) and energy efficiency (EE, 84%) than Nafion 117 membrane (CE, 92% and EE, 78%) at current density of 80 mA cm-2. Besides, the HSPAEK membrane shows super stable CE and EE as well as excellent discharge capacity retention (83%) during 100 cycles life test. After being soaked in 1.5 mol L-1 VO2+ solution for 21 days, the weight loss of HSPAEK membrane and the amount of VO2+ reduced from VO2+ are only 0.26% and 0.7%, respectively, indicating the superior chemical stability of the membrane.

  7. Investigations of effects of environmental factors in unfolding/refolding pathway of proteins on 8-anilino-1-naphthalene-sulfonic acid (ANS) fluorescence

    NASA Astrophysics Data System (ADS)

    Qu, Peng; Lu, Hua; Yan, Shancheng; Zhou, Dequan; Lu, Zuhong

    2009-11-01

    The effects of various environmental factors in unfolding/refolding pathway of proteins on ANS fluorescence were investigated. In phosphate buffer of pH 7.4, ANS bound cetyl trimethyl ammonium bromide (CTMAB) and resulted in significant increase of ANS fluorescence and a sudden blue-shift in emission maximum wavelength. Sodium dodecyl sulfate (SDS) caused less increase in ANS fluorescence and less blue-shift in emission maximum wavelength than CTMAB and Tween 20. Tween 20, urea, polyethylene glycol 8000 (PEG 8000) and glycerol which contains hydrophobic groups also enhanced ANS fluorescence and caused their emission maximum wavelength blue-shift. For guanidine hydrochloride (GdmCl), due to its shorter hydrophobic chain, it caused less increase in ANS fluorescence and less decrease in emission maximum wavelength than CTMAB although GdmCl also has a positive charge. The results demonstrated the need for caution in interpreting enhancement of ANS fluorescence as an evidence for the existence of partially folded protein intermediates.

  8. Nuclear Magnetic Resonance Identification of New Sulfonic Acid Metabolites of Chloroacetanilide Herbicides

    USGS Publications Warehouse

    Morton, M.D.; Walters, F.H.; Aga, D.S.; Thurman, E.M.; Larive, C.K.

    1997-01-01

    The detection of the sulfonic acid metabolites of the chloroacetanilide herbicides acetochlor, alachlor, butachlor, propachlor, and, more recently, metolachlor in surface and ground water suggests that a common mechanism for dechlorination exists via the glutathione conjugation pathway. The identification of these herbicides and their metabolites is important due to growing public awareness and concern about pesticide levels in drinking water. Although these herbicides are regulated, little is known about the fate of their metabolites in soil. The sulfonic acid metabolites were synthesized by reaction of the parent compounds with an excess of sodium sulfite. Acetochlor, alachlor, butachlor, metolachlor, and propachlor and their sulfonic acid metabolites were studied by nuclear magnetic resonance spectroscopy and fast atom bombardment mass spectrometry. This paper provides a direct method for the preparation and characterization of these compounds that will be useful in the analysis and study of chloracetanilide herbicides and their metabolites.

  9. Proton conducting sol-gel sulfonated membranes produced from 2-allylphenol, 3-glycidoxypropyl trimethoxysilane and tetraethyl orthosilicate

    NASA Astrophysics Data System (ADS)

    Mosa, J.; Durán, A.; Aparicio, M.

    An important research area in proton exchange membrane fuel cells (PEMFC) is devoted to the development of low cost membranes able to work at temperatures higher than 100 °C. In this work, homogeneous, transparent and crack-free hybrid membranes have been synthesized using tetraethyl orthosilicate (TEOS), 3-glycidoxipropyl trimethoxysilane (GPTMS) and 2-allylphenol (AP) as precursors. The synthesis of proton conducting membranes was performed by a post-sulfonation method using trimethylsilyl chlorosulfonate as a mild sulfonating agent. The water retention properties provided by sulfonate and hydroxyl groups and the high porosity leads to relatively high proton conductivity (maximum values around 1.3 × 10 -3 S cm -1 at 140 °C and 100% RH) for membranes treated at 180 °C and sulfonated for 2 h.

  10. Syntheses, characterizations and crystal structures of two new lead(II) amino and carboxylate-sulfonates with a layered and a pillared layered structure

    NASA Astrophysics Data System (ADS)

    Yuan, Yan-Ping; Mao, Jiang-Gao; Song, Jun-Ling

    2004-03-01

    Reactions of lead(II) acetate with m-aminobenzenesulfonic acid (H L1) and 5-sulfoisophthalic acid (H 3L2) afforded two new lead(II) sulfonates, Pb( L1) 21 and Pb 2( L2)( μ3-OH)(H 2O) 2. In compound 1, the lead(II) ion is eight-coordinated by two sulfonate groups bidentately, two sulfonate groups unidentately and two amino groups from six ligands. Each L1 ligand is tetradentate and bridges with three Pb(II) ions. The interconnection of the Pb(II) ions via bridging sulfonate ligands resulted in <100> and <200> layers. In compound 2, one Pb(II) ion is six-coordinated by a carboxylate group bidentately, by two carboxylate groups unidentately, by a sulfonate oxygen atom and by an OH anion, whereas the other one is six-coordinated by a bidentate chelating carboxylate group, two μ3-OH anions, a sulfonate oxygen atom and an aqua ligand. The interconnection of irregular PbO 6 polyhedra via carboxylate-sulfonate ligands resulted in the formation of a pillared layered structure with the 2D layer being formed; the lead(II) ions, hydroxyl groups, carboxylate and sulfonate groups and the benzene ring as the pillar agent.

  11. Colonic necrosis and perforation due to calcium polystyrene sulfonate in a uraemic patient: a case report

    PubMed Central

    Yazici, Halil; Gulluoglu, Mine G.; Yegen, Gulcin; Turkmen, Aydin

    2011-01-01

    Sodium or calcium polystyrene sulfonate (Kayexalate or analog) is an ion-exchange resin commonly used to treat hyperkalaemia in patients with chronic kidney disease. It is known to cause digestive complications, such as nausea, vomiting and constipation. Although rare, colonic necrosis and perforation are very severe complications associated with the medication. In this case report, we present a case of calcium polystyrene sulfonate-induced colonic necrosis and perforation to remind clinicians of this rare, but dangerous, toxicity associated with this commonly used medication. PMID:25984206

  12. Colonic necrosis and perforation due to calcium polystyrene sulfonate in a uraemic patient: a case report.

    PubMed

    Akagun, Tulin; Yazici, Halil; Gulluoglu, Mine G; Yegen, Gulcin; Turkmen, Aydin

    2011-12-01

    Sodium or calcium polystyrene sulfonate (Kayexalate or analog) is an ion-exchange resin commonly used to treat hyperkalaemia in patients with chronic kidney disease. It is known to cause digestive complications, such as nausea, vomiting and constipation. Although rare, colonic necrosis and perforation are very severe complications associated with the medication. In this case report, we present a case of calcium polystyrene sulfonate-induced colonic necrosis and perforation to remind clinicians of this rare, but dangerous, toxicity associated with this commonly used medication.

  13. Ruthenium(II)-catalyzed oxidative C-H alkenylations of sulfonic acids, sulfonyl chlorides and sulfonamides.

    PubMed

    Ma, Wenbo; Mei, Ruhuai; Tenti, Giammarco; Ackermann, Lutz

    2014-11-10

    Twofold C-H functionalization of aromatic sulfonic acids was achieved with an in situ generated ruthenium(II) catalyst. The optimized cross-dehydrogenative alkenylation protocol proved applicable to differently substituted arenes and a variety of alkenes, including vinyl arenes, sulfones, nitriles and ketones. The robustness of the ruthenium(II) catalyst was demonstrated by the chemoselective oxidative olefination of sulfonamides as well as sulfonyl chlorides. Mechanistic studies provided support for a reversible, acetate-assisted C-H ruthenation, along with a subsequent olefin insertion.

  14. Preparation of Sulfonated Poly(aryl ether sulfone) Electrospun Mat/Phosphosilicate Composite Proton Exchange Membrane

    NASA Astrophysics Data System (ADS)

    Wang, Limei; Dou, Liyan; Guan, Guoying

    2017-03-01

    Side-chain-type sulfonated poly(aryl ether sulfone) (SPES) was synthesized and then electrospun into mats. Phosphosilicate glass (PS) via in situ sol-gel synthesis was enclosed in the mats to form a new reinforced composite membrane. The SPES/PS composite membranes showed satisfactory dimensional change behavior with varying humidity. Especially, the composite membrane exhibits excellent proton conductivity at harsh measurement conditions of low humidity at 80°C. The composite membrane with outstanding combined properties has potential applications for high temperature polymer electrolyte membrane fuel cells.

  15. Preparation of Sulfonated Poly(aryl ether sulfone) Electrospun Mat/Phosphosilicate Composite Proton Exchange Membrane

    NASA Astrophysics Data System (ADS)

    Wang, Limei; Dou, Liyan; Guan, Guoying

    2017-01-01

    Side-chain-type sulfonated poly(aryl ether sulfone) (SPES) was synthesized and then electrospun into mats. Phosphosilicate glass (PS) via in situ sol-gel synthesis was enclosed in the mats to form a new reinforced composite membrane. The SPES/PS composite membranes showed satisfactory dimensional change behavior with varying humidity. Especially, the composite membrane exhibits excellent proton conductivity at harsh measurement conditions of low humidity at 80°C. The composite membrane with outstanding combined properties has potential applications for high temperature polymer electrolyte membrane fuel cells.

  16. Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. Tenth quarterly report

    SciTech Connect

    Krawiec, S.

    1992-02-07

    The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate (``4S``) pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a ``fermentor`` for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.

  17. Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. [Pseudomonas, Thiobacillus, Rhodococcus

    SciTech Connect

    Krawiec, S.

    1992-02-07

    The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate ( 4S'') pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a fermentor'' for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.

  18. Sulfonimide-containing poly(arylene ether)s and poly(arylene ether sulfone)s, methods for producing the same, and uses thereof

    DOEpatents

    Hofmann, Michael A.

    2006-11-14

    The present invention is directed to sulfonimide-containing polymers, specifically sulfonimide-containing poly(arylene ether)s and sulfonimide-containing poly(arylene ether sulfone)s, and processes for making the sulfonimide-containing poly(arylene ether)s and sulfonimide-containing poly(arylene ether sulfone)s, for use conductive membranes and fuel cells.

  19. Nanostructured membranes and electrodes with sulfonic acid functionalized carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Tripathi, Bijay P.; Schieda, M.; Shahi, Vinod K.; Nunes, Suzana P.

    Herein we report the covalent functionalization of multiwall carbon nanotubes by grafting sulfanilic acid and their dispersion into sulfonated poly(ether ether ketone). The nanocomposites were explored as an option for tuning the proton and electron conductivity, swelling, water and alcohol permeability aiming at nanostructured membranes and electrodes for application in alcohol or hydrogen fuel cells and other electrochemical devices. The nanocomposites were extensively characterized, by studying their physicochemical and electrochemical properties. They were processed as self-supporting films with high mechanical stability, proton conductivity of 4.47 × 10 -2 S cm -1 at 30 °C and 16.8 × 10 -2 S cm -1 at 80 °C and 100% humidity level, electron conductivity much higher than for the plain polymer. The methanol permeability could be reduced to 1/20, keeping water permeability at reasonable values. The ratio of bound water also increases with increasing content of sulfonated filler, helping in keeping water in the polymer in conditions of low external humidity level.

  20. Synthesis, Characterization, and Catalytic Activity of Sulfonated Carbon-Based Catalysts Derived From Rubber Tree Leaves and Pulp and Paper Mill Waste

    NASA Astrophysics Data System (ADS)

    Janaun, J.; Sinin, E.; Hiew, S. F.; Kong, A. M. T.; Lahin, F. A.

    2016-06-01

    Sulfonated carbon-based catalysts derived from rubber tree leaves, and pulp and paper mill waste were synthesized and characterized. Three types of catalyst synthesized were sulfonated rubber tree leaves (S-RTL), pyrolysed sludge char (P-SC) and sulfonated sludge char (S-SC). Sulfonated rubber tree leaves (S-RTL) and sulfonated sludge char (S-SC) were prepared through pyrolysis followed by functionalization via sulfonation process whereas, P- SC was only pyrolyzed without sulfonation. The characterization results indicated sulfonic acids, hydroxyl, and carboxyl moieties were detected in S-RTL and S-SC, but no sulfonic acid was detected in P-SC. Total acidity test showed S-RTL had the highest value followed by S-SC and P-SC. The thermal stability of S-RTL and S-SC were up to 230oC as the loss was associated with the decomposition of sulfonic acid group, whereas, P-SC showed higher stability than the S-RTL and S-SC. Morphology analysis showed that S-RTL consisted of an amorphous carbon structure, and a crystalline structure for P-SC and S-SC. Furthermore, traces of metal components were also detected on all of the catalysts. The catalyst catalytic activity was tested through esterification of oleic acid with methanol. The results showed that the reaction using S-RTL catalyst produced the highest conversion (99.9%) followed by P-SC (88.4%) and lastly S-SC (82.7%). The synthesized catalysts showed high potential to be used in biodiesel production.

  1. Acid-mediated formation of trifluoromethyl sulfonates from sulfonic acids and a hypervalent iodine trifluoromethylating agent.

    PubMed

    Koller, Raffael; Huchet, Quentin; Battaglia, Philip; Welch, Jan M; Togni, Antonio

    2009-10-28

    A variety of sulfonic acids have been trifluoromethylated using 1-trifluoromethyl-1,2-benziodoxol-3(1H)-one under mild conditions in good to excellent yields. Initial mechanistic investigations of this reaction show a clean second-order kinetics and only very weak substrate electronic effects.

  2. A new sesquiterpene lactone with sulfonic acid group from Saussurea lappa.

    PubMed

    Yin, Hong-Quan; Hua, Hui-Ming; Fu, Hong-Wei; Qi, Xiu-Lan; Li, Wen; Sha, Yi; Pei, Yue-Hu

    2007-01-01

    A new sesquiterpene lactone with an unusual sulfonic acid group, 13-sulfo-dihydrodehydrocostus lactone (1), was isolated from the roots of Saussurea lappa C. (Compositae), together with a known lignan (2). The structure of 1 was characterized on the basis of spectral evidence including 2DNMR studies. Compound 2 was obtained from this plant for the first time.

  3. Effects of prenatal exposure to perfluorooctane sulfonate on the developing lung in the rat

    EPA Science Inventory

    Perfluorooctane sulfonate (PFOS), an environmentally stable industrial and household compound, has been detected in human and wildlife sera. Chronic prenatal exposure to PFOS in rodents leads to mortality in newborns within hours to days after birth. We have demonstrated that tr...

  4. POLYSTYRENE SULFONIC ACID CATALYZED GREENER SYNTHESIS OF HYDRAZONES IN AQUEOUS MEDIUM USING MICROWAVES

    EPA Science Inventory

    An environmentally benign aqueous protocol for the synthesis of cyclic, bi-cyclic, and heterocyclic hydrazones using polystyrene sulfonic acid (PSSA) as a catalyst has been developed; the simple reaction proceeds efficiently in water in the absence of any organic solvent under mi...

  5. Double lawton SN2'addition to epoxyvinyl sulfones: selective construction of the stereotetrads of aplyronine A.

    PubMed

    El-Awa, Ahmad; Fuchs, Philip

    2006-07-06

    [reaction: see text] Enantiopure epoxyvinyl sulfones function as templates for the diastereoselective construction of the three stereotetrads of aplyronine A. Lawton S(N)2' addition of 3,5-dimethylpyrazole followed by its displacement in an alcohol-directed Lawton S(N)2' reaction establishes the required product stereochemistry with high selectivity.

  6. Exposure to perfluorooctane sulfonate during pregnancy in rat and mouse. I: maternal and prenatal evaluations

    EPA Science Inventory

    Abstract: The maternal and developmental toxicities of perfluorooctane sulfonate (PFOS, C8F17SO3-) were evaluated in the rat and mouse. PFOS is an environmentally persistent compound used as a surfactant and occurs as a degradation product of both perfluorooctane sulfonyl fluorid...

  7. Boiling significantly promotes photodegradation of perfluorooctane sulfonate.

    PubMed

    Lyu, Xian-Jin; Li, Wen-Wei; Lam, Paul K S; Yu, Han-Qing

    2015-11-01

    The application of photochemical processes for perfluorooctane sulfonate (PFOS) degradation has been limited by a low treatment efficiency. This study reports a significant acceleration of PFOS photodegradation under boiling condition compared with the non-boiling control. The PFOS decomposition rate increased with the increasing boiling intensity, but declined at a higher hydronium level or under oxygenation. These results suggest that the boiling state of solution resulted in higher effective concentrations of reactants at the gas-liquid interface and enhanced the interfacial mass transfer, thereby accelerating the PFOS decomposition. This study broadens our knowledge of PFOS photodegradation process and may have implications for development of efficient photodegradation technologies.

  8. Synthesis of cyclic sulfones by ring-closing metathesis.

    PubMed

    Yao, Qingwei

    2002-02-07

    A general and highly efficient synthesis of cyclic sulfones based on ring-closing metathesis has been developed. The synthetic utility of the resulting cyclic sulfones was demonstrated by their participation in stereoselective Diels-Alder reactions and transformation to cyclic dienes by the Ramberg-Bäcklund reaction.

  9. 21 CFR 177.2500 - Polyphenylene sulfone resins.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... consist of basic resin produced by reacting polyphenylene sulfide with peracetic acid such that the... sulfide used to manufacture polyphenylene sulfone is prepared by the reaction of sodium sulfide and p... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Polyphenylene sulfone resins. 177.2500 Section...

  10. Sulfonated Nanoplates in Proton Conducting Membranes for Fuel Cells

    SciTech Connect

    Chen, W.F.; Ni’mah, H.; Yu-Cheng Shen, Y.-C.; Kuo, P.-L.

    2011-09-29

    Surface-functionalized nanoplates are synthesized by anchoring sulfonic acid containing siloxanes on zirconium phosphate, and in turn blended with Nafion to fabricate proton conducting membranes. The effects of these sulfonated nanoplates on proton conduction, hydro-characteristics and fuel cell performance are reported.

  11. 40 CFR 721.1625 - Alkylbenzene sulfonate, amine salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Alkylbenzene sulfonate, amine salt... Substances § 721.1625 Alkylbenzene sulfonate, amine salt. (a) Chemical substance and significant new uses... salt (PMN P-90-456) is subject to reporting under this section for the significant new use described...

  12. 40 CFR 721.1625 - Alkylbenzene sulfonate, amine salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkylbenzene sulfonate, amine salt... Substances § 721.1625 Alkylbenzene sulfonate, amine salt. (a) Chemical substance and significant new uses... salt (PMN P-90-456) is subject to reporting under this section for the significant new use described...

  13. Synthesis of basic and overbasic sulfonate detergent additives

    SciTech Connect

    Abou El Naga, H.H.; Abd El-Azim, W.M.; Bendary, S.A.; Awad, N.G.

    1993-12-01

    Heavy alkylbenzene, which accumulates as a by-product from linear alkylbenzene synthesis, is evaluated as a starting material for preparation of basic and over basic sulfonate detergent additives. Chemical structure analysis showed that this by-product contains several components in different proportions. Most of these components, as traced via mass spectrometry, showed the presence of paraffinic side chains within the carbon range C{sub 11}--C{sub 22}. Accordingly, sulfonation conditions for it were adjusted to optimize the reaction yield and sulfonic quality. Neutralization of the sulfonic acid was carried out by adding CaO in the presence of methanol as a promoter. Preparation of over basic sulfonate was run via a carbonation process at 55--60 C. Evaluations of synthesized basic calcium sulfonate in comparison to a commercial additive is supported by its efficiency as a detergent additive. The synthesized product has a higher total base number and Ca content than those for the commercial one. On the other hand, evaluation of the synthesized overbasic calcium sulfonate compared with overbasic commercial additives with medium and high alkalinity indicated that the synthesized product can be classified as overbasic calcium sulfonate with medium alkalinity, good dispersive power, and detergent efficiency.

  14. 21 CFR 177.2210 - Ethylene polymer, chloro-sulfonated.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ethylene polymer, chloro-sulfonated. 177.2210... (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use Only as Components of Articles Intended for Repeated Use § 177.2210 Ethylene polymer, chloro-sulfonated. Ethylene polymer, chlorosulfonated...

  15. Assembling structures and dynamics properties of perfluorooctane sulfonate (PFOS) at water-titanium oxide interfaces.

    PubMed

    He, Guangzhi; Pan, Gang; Zhang, Meiyi

    2013-09-01

    The surface-associated structures and growth modes of perfluorooctane sulfonate (PFOS) at water-rutile TiO2 interfaces were defined by molecular dynamics (MD) simulations. The results showed that a compact PFOS layer was generated at the rutile surfaces, and the assembling structures and dynamic profiles were crystal-face-dependent. PFOS molecules were attached to the (110) and (001) surfaces mainly by the sulfonate headgroups. A well-defined monolayer was formed on the (110) surface with the perfluorinated alkyl chains nearly perpendicular to the substrate, whereas the C-F chains were inclined at an angle (30-75°) and formed a hemicylinder-like configuration on the (001) surface. On the other hand, the perfluorinated amphiphiles interacted with the (100) plane through both the sulfonate headgroups (relatively strong electrostatic attraction) and the C-F tailgroups (weak van der Waals forces) and yielded an irregular assembling pattern. Water molecules were mostly concentrated more than 17.0 Å away from the solid surfaces and formed a continuous solvent layer, suggesting the super hydrophobicity of perfluorinated alkyl chains. A counterion-bridging mechanism suggested in surfactant adsorption was observed at the molecular scale, where the sulfonate headgroups were linked together by the potassium ions at the surfaces and caused the formation of surface aggregates.

  16. Effective and selective bisphenol A synthesis on a layered silicate with spatially arranged sulfonic acid.

    PubMed

    Ide, Yusuke; Kagawa, Noriko; Itakura, Masaya; Imae, Ichiro; Sadakane, Masahiro; Sano, Tsuneji

    2012-04-01

    The silylated derivatives of a layered alkali silicate, magadiite, modified with propylsulfonic or arylsulfonic acid were synthesized and used as catalysts for an acid-catalyzed condensation of phenol with acetone. The propylsulfonated magadiites with a different amount of the attached silyl group were synthesized by the silylation of the dodecylammonium-exchanged magadiite with the tuned amount of 3-(mercaptopropyl)trimethoxysilane and the subsequent oxidation of the attached thiol to sulfonic acid. The arylsulfonated magadiite was synthesized by the silylation of the dodecylammonium-exchanged magadiite with 2-(4-chlorosulfonylphenyl)ethyltrimethoxysilane and the subsequent hydrolysis of the attached sulfonyl chloride to sulfonic acid. The X-ray diffraction (XRD) patterns and elemental mappings of the products, and the photoluminescent spectra of the Eu(3+)-exchanged products suggested that propylsulfonic or arylsulfonic acid was homogeneously distributed in the interlayer space. When all the sulfonated materials were used as an acid catalyst for condensation between phenol and acetone, p,p' bisphenol A selectively formed over the o,p' isomer, and higher yield and selectivity were attained on the catalysts with larger amount of the attached sulfonic acid. When the interlayer space of the propylsulfonated magadiite was expanded by the co-attachment of octadecylsilyl group, lower selectivity was obtained. The arylsulfonated magadiite showed considerably higher p,p' bisphenol A yield than the propylsulfonated magadiites.

  17. Controlling Structure in Sulfonated Block Copolymer Membranes

    NASA Astrophysics Data System (ADS)

    Truong, Phuc; Stein, Gila; Strzalka, Joe

    2015-03-01

    In many ionic block copolymer systems, the strong incompatibility between ionic and non-ionic segments will trap non-equilibrium structures in the film, making it difficult to engineer the optimal domain sizes and transport pathways. The goal of this work is to establish a framework for controlling the solid-state structure of sulfonated pentablock copolymer membranes. They have ABCBA block sequence, where A is poly(t-butyl styrene), B is poly(hydrogenated isoprene), and C is poly(styrene sulfonate). To process into films, the polymer is dissolved in toluene/n-propanol solvent mixtures, where the solvent proportions and the polymer loading were both varied. Solution-state structure was measured with small angle X-ray scattering (SAXS). We detected micelles with radii that depend on the solvent composition and polymer loading. Film structure was measured with grazing-incidence SAXS, which shows (i) domain periodicity is constant throughout film thickness; (ii) domain periodicity depends on solvent composition and polymer loading, and approximately matches the micelle radii in solutions. The solid-state packing is consistent with a hard sphere structure factor. Results suggest that solid-state structure can be tuned by manipulating the solution-state self-assembly.

  18. Inactivation of a class A and a class C β-lactamase by 6β-(hydroxymethyl)penicillanic acid sulfone

    PubMed Central

    Papp-Wallace, Krisztina M.; Bethel, Christopher R.; Gootz, Thomas D.; Shang, Wenchi; Stroh, Justin; Lau, William; McLeod, Dale; Price, Loren; Marfat, Anthony; Distler, Anne; Drawz, Sarah M.; Chen, Hansong; Harry, Emily; Nottingham, Micheal; Carey, Paul R.; Buynak, John D.; Bonomo, Robert A.

    2012-01-01

    β-Lactamase inhibitors (clavulanic acid, sulbactam, and tazobactam) contribute significantly to the longevity of the β-lactam antibiotics used to treat serious infections. In the quest to design more potent compounds and to understand the mechanism of action of known inhibitors, 6β-(hydroxymethyl)penicillanic acid sulfone (6β-HM-sulfone) was tested against isolates expressing the class A TEM-1 β-lactamase and a clinically important variant of the AmpC cephalosporinase of Pseudomonas aeruginosa, PDC-3. The addition of the 6β-HM-sulfone inhibitor to ampicillin was highly effective. 6β-HM-sulfone inhibited TEM-1 with an IC50 of 12 ± 2 nM and PDC-3 with an IC50 of 180 ± 36 nM, and displayed lower partition ratios than commercial inhibitors, with partition ratios (kcat/kinact) equal to 174 for TEM-1 and 4 for PDC-3. Measured for 20 h, 6β-HM-sulfone demonstrated rapid, first-order inactivation kinetics with the extent of inactivation being related to the concentration of inhibitor for both TEM-1 and PDC-3. Using mass spectrometry to gain insight into the intermediates of inactivation of this inhibitor, 6β-HM-sulfone was found to form a major adduct of +247 ± 5 Da with TEM-1 and +245 ± 5 Da with PDC-3, suggesting that the covalently bound, hydrolytically stabilized acyl-enzyme has lost a molecule of water (H–O–H). Minor adducts of +88 ± 5 Da with TEM-1 and +85 ± 5 Da with PDC-3 revealed that fragmentation of the covalent adduct can result but appeared to occur slowly with both enzymes. 6β-HM-sulfone is an effective and versatile β-lactamase inhibitor of representative class A and C enzymes. PMID:22155308

  19. Red electroluminescence of ruthenium sensitizer functionalized by sulfonate anchoring groups.

    PubMed

    Shahroosvand, Hashem; Abbasi, Parisa; Mohajerani, Ezeddin; Janghouri, Mohammad

    2014-06-28

    We have synthesized five novel Ru(ii) phenanthroline complexes with an additional aryl sulfonate ligating substituent at the 5-position [Ru(L)(bpy)2](BF4)2 (1), [Ru(L)(bpy)(SCN)2] (2), [Ru(L)3](BF4)2 (3), [Ru(L)2(bpy)](BF4)2 (4) and [Ru(L)(BPhen)(SCN)2] (5) (where L = 6-one-[1,10]phenanthroline-5-ylamino)-3-hydroxynaphthalene 1-sulfonic, bpy = 2,2'-bipyridine, BPhen = 4,7-diphenyl-1,10-phenanthroline), as both photosensitizers for oxide semiconductor solar cells (DSSCs) and light emitting diodes (LEDs). The absorption and emission maxima of these complexes red shifted upon extending the conjugation of the phenanthroline ligand. Ru phenanthroline complexes exhibit broad metal to ligand charge transfer-centered electroluminescence (EL) with a maximum near 580 nm. Our results indicated that a particular structure (2) can be considered as both DSSC and OLED devices. The efficiency of the LED performance can be tuned by using a range of ligands. Device (2) has a luminance of 550 cd m(-2) and maximum efficiency of 0.9 cd A(-1) at 18 V, which are the highest values among the five devices. The turn-on voltage of this device is approximately 5 V. The role of auxiliary ligands in the photophysical properties of Ru complexes was investigated by DFT calculation. We have also studied photovoltaic properties of dye-sensitized nanocrystalline semiconductor solar cells based on Ru phenanthroline complexes and an iodine redox electrolyte. A solar energy to electricity conversion efficiency (η) of 0.67% was obtained for Ru complex (2) under standard AM 1.5 irradiation with a short-circuit photocurrent density (Jsc) of 2.46 mA cm(-2), an open-circuit photovoltage (Voc) of 0.6 V, and a fill factor (ff) of 40%, which are all among the highest values for ruthenium sulfonated anchoring groups reported so far. Monochromatic incident photon to current conversion efficiency was 23% at 475 nm. Photovoltaic studies clearly indicated dyes with two SCN substituents yielded a higher Jsc for the

  20. Synthesis of sulfonated porous carbon nanospheres solid acid by a facile chemical activation route

    NASA Astrophysics Data System (ADS)

    Chang, Binbin; Guo, Yanzhen; Yin, Hang; Zhang, Shouren; Yang, Baocheng

    2015-01-01

    Generally, porous carbon nanospheres materials are usually prepared via a template method, which is a multi-steps and high-cost strategy. Here, we reported a porous carbon nanosphere solid acid with high surface area and superior porosity, as well as uniform nanospheical morphology, which prepared by a facile chemical activation with ZnCl2 using resorcinol-formaldehyde (RF) resins spheres as precursor. The activation of RF resins spheres by ZnCl2 at 400 °C brought high surface area and large volume, and simultaneously retained numerous oxygen-containing and hydrogen-containing groups due to the relatively low processing temperature. The presence of these functional groups is favorable for the modification of -SO3H groups by a followed sulfonation treating with sulphuric acid and organic sulfonic acid. The results of N2 adsorption-desorption and electron microscopy clearly showed the preservation of porous structure and nanospherical morphology. Infrared spectra certified the variation of surface functional groups after activation and the successful modification of -SO3H groups after sulfonation. The acidities of catalysts were estimated by an indirect titration method and the modified amount of -SO3H groups were examined by energy dispersive spectra. The results suggested sulfonated porous carbon nanospheres catalysts possessed high acidities and -SO3H densities, which endowed their significantly catalytic activities for biodiesel production. Furthermore, their excellent stability and recycling property were also demonstrated by five consecutive cycles.

  1. Wine metabolomics reveals new sulfonated products in bottled white wines, promoted by small amounts of oxygen.

    PubMed

    Arapitsas, Panagiotis; Ugliano, Maurizio; Perenzoni, Daniele; Angeli, Andrea; Pangrazzi, Paolo; Mattivi, Fulvio

    2016-01-15

    The impact of minute amounts of oxygen in the headspace on the post-bottling development of wine is generally considered to be very important, since oxygen can either damage or improve the quality of wine. This project aimed to gain new experimental evidence about the chemistry of the interaction between wine and oxygen. The experimental design included 216 bottles of 12 different white wines produced from 6 different cultivars (Inzolia, Muller Thurgau, Chardonnay, Grillo, Traminer and Pinot gris). Half of them were bottled using the standard industrial process with inert headspace and the other half without inert gas and with extra headspace. After 60 days of storage at room temperature, the wines were analysed using an untargeted LC-MS method. The use of a detailed holistic analysis workflow, with several levels of quality control and marker selection, gave 35 metabolites putatively induced by the different amounts of oxygen. These metabolite markers included ascorbic acid, tartaric acid and various sulfonated compounds observed in wine for the first time (e.g. S-sulfonated cysteine, glutathione and pantetheine; and sulfonated indole-3-lactic acid hexoside and tryptophol). The consumption of SO2 mediated by these sulfonation reactions was promoted by the presence of higher levels of oxygen on bottling.

  2. Perfluorooctane sulfonate induces apoptosis in N9 microglial cell line.

    PubMed

    Zhang, Ling; Li, Yuan-yuan; Zeng, Huai-cai; Li, Miao; Wan, Yan-Jian; Schluesener, Hermann J; Zhang, Zhi-yuan; Xu, Shun-qing

    2011-03-01

    Perfluorooctane sulfonate (PFOS) is an environmental persistent acid found at low levels in human, wildlife, and environmental media samples. To study the apoptosis effects of PFOS on microglia, murine N9 cell line was used as a model in current research. The results showed that PFOS could reduce the cell viability significantly, and the cellular apoptosis induced by PFOS was closely accompanied with dissipation of mitochondria membrane potential, upregulation messenger RNAs (mRNAs) of p53, Bax, caspase 9, and caspase 3, and decreased expression of Bcl-2 mRNA. These results suggested that PFOS could disturb homeostasis of N9 cells, impact mitochondria, and affect gene expression of apoptotic regulators, all of which resulted in a start-up of apoptosis.

  3. Chitin nanowhisker-supported sulfonated poly(ether sulfone) proton exchange for fuel cell applications.

    PubMed

    Zhang, Chan; Zhuang, Xupin; Li, Xiaojie; Wang, Wei; Cheng, Bowen; Kang, Weimin; Cai, Zhanjun; Li, Mengqin

    2016-04-20

    To balance the relationship among proton conductivity and mechanic strength of sulfonated poly(ether sulfone) (SPES) membrane, chitin nanowhisker-supported nanocomposite membranes were prepared by incorporating whiskers into SPES. The as-prepared chitin whiskers were prepared by 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) mediated oxidation of α-chitin from crab shells. The structure and properties of the composite membranes were examined as proton exchange membrane (PEM). Results showed that chitin nanowhiskers were dispersed incompactly in the SPES matrix. Thermal stability, mechanical properties, water uptake and proton conductivity of the nanocomposite films were improved from those of the pure SPES film with increasing whisker content, which ascribed to strong interactions between whiskers and between SPES molecules and chitin whiskers via hydrogen bonding. These indicated that composition of filler and matrix got good properties and whisker-supported membranes are promising materials for PEM.

  4. Synthesis of sulfonated porous carbon nanospheres solid acid by a facile chemical activation route

    SciTech Connect

    Chang, Binbin Guo, Yanzhen; Yin, Hang; Zhang, Shouren; Yang, Baocheng

    2015-01-15

    Generally, porous carbon nanospheres materials are usually prepared via a template method, which is a multi-steps and high-cost strategy. Here, we reported a porous carbon nanosphere solid acid with high surface area and superior porosity, as well as uniform nanospheical morphology, which prepared by a facile chemical activation with ZnCl{sub 2} using resorcinol-formaldehyde (RF) resins spheres as precursor. The activation of RF resins spheres by ZnCl{sub 2} at 400 °C brought high surface area and large volume, and simultaneously retained numerous oxygen-containing and hydrogen-containing groups due to the relatively low processing temperature. The presence of these functional groups is favorable for the modification of –SO{sub 3}H groups by a followed sulfonation treating with sulphuric acid and organic sulfonic acid. The results of N{sub 2} adsorption–desorption and electron microscopy clearly showed the preservation of porous structure and nanospherical morphology. Infrared spectra certified the variation of surface functional groups after activation and the successful modification of –SO{sub 3}H groups after sulfonation. The acidities of catalysts were estimated by an indirect titration method and the modified amount of –SO{sub 3}H groups were examined by energy dispersive spectra. The results suggested sulfonated porous carbon nanospheres catalysts possessed high acidities and –SO{sub 3}H densities, which endowed their significantly catalytic activities for biodiesel production. Furthermore, their excellent stability and recycling property were also demonstrated by five consecutive cycles. - Graphical abstract: Sulfonated porous carbon nanospheres with high surface area and superior catalytic performance were prepared by a facile chemical activation route. - Highlights: • Porous carbon spheres solid acid prepared by a facile chemical activation. • It owns high surface area, superior porosity and uniform spherical morphology. • It possesses

  5. 21 CFR 172.824 - Sodium mono- and dimethyl naphthalene sulfonates.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium mono- and dimethyl naphthalene sulfonates... sulfonates. The food additive sodium mono- and dimethyl naphthalene sulfonates may be safely used in... statement declaring the presence of sodium mono- and dimethyl naphthalene sulfonates....

  6. 21 CFR 172.824 - Sodium mono- and dimethyl naphthalene sulfonates.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium mono- and dimethyl naphthalene sulfonates... sulfonates. The food additive sodium mono- and dimethyl naphthalene sulfonates may be safely used in... statement declaring the presence of sodium mono- and dimethyl naphthalene sulfonates....

  7. Electrical conductivity of sulfonated poly(ether ether ketone) based composite membranes containing sulfonated polyhedral oligosilsesquioxane

    NASA Astrophysics Data System (ADS)

    Celso, Fabricio; Mikhailenko, Serguei D.; Rodrigues, Marco A. S.; Mauler, Raquel S.; Kaliaguine, Serge

    2016-02-01

    Composite proton exchange membranes (PEMs) intended for fuel cell applications were prepared by embedding of various amounts of dispersed tri-sulfonic acid ethyl POSS (S-Et-POSS) and tri-sulfonic acid butyl POSS (S-Bu-POSS) in thin films of sulfonated poly ether-ether ketone. The electrical properties of the PEMs were studied by Impedance spectroscopy and it was found that their conductivity σ changes with the filler content following a curve with a maximum. The water uptake of these PEMs showed the same dependence. The investigation of initial isolated S-POSS substances revealed the properties of typical electrolytes, which however in both cases possessed low conductivities of 1. 17 × 10-5 S cm-1 (S-Et-POSS) and 3.52 × 10-5 S cm-1 (S-Bu-POSS). At the same time, the insoluble in water S-POSS was found forming highly conductive interface layer when wetted with liquid water and hence producing a strong positive impact on the conductivity of the composite PEM. Electrical properties of the composites were analysed within the frameworks of effective medium theory and bounding models, allowing to evaluate analytically the range of possible conductivity values. It was found that these approaches produced quite good approximation of the experimental data and constituted a fair basis for interpretation of the observed relationship.

  8. Alkyl phosphonic acids and sulfonic acids in the Murchison meteorite

    NASA Technical Reports Server (NTRS)

    Cooper, George W.; Onwo, Wilfred M.; Cronin, John R.

    1992-01-01

    Homologous series of alkyl phosphonic acids and alkyl sulfonic acids, along with inorganic orthophosphate and sulfate, are identified in water extracts of the Murchison meteorite after conversion to their t-butyl dimethylsilyl derivatives. The methyl, ethyl, propyl, and butyl compounds are observed in both series. Five of the eight possible alkyl phosphonic acids and seven of the eight possible alkyl sulfonic acids through C4 are identified. Abundances decrease with increasing carbon number as observed of other homologous series indigenous to Murchison. Concentrations range downward from approximately 380 nmol/gram in the alkyl sulfonic acid series, and from 9 nmol/gram in the alkyl phosphonic acid series.

  9. Comparison of Different Synthetic Routes for Sulfonation of Polyaniline

    DTIC Science & Technology

    1992-06-29

    sulfonated -olyanaiine (SPAN), the first self protonic acid doped polyaniline , was reported.4 In order to establish the relationships between a variety of...FOR SULFONATION OF POLYANILINE " 6. AUTHOR(S) • G--N00014-90-J- 1559 J. Yue, G. Gordon a"-I AJ. Epstein 7. PERFORMING ORGANIZATION NAMI(S) AND REPORT...Appeved kw puklie rela"MI , ,mum 200 woros) Polyanilines containing sulfonic groups covalently bonded to the back- z•um bone were synthesized from

  10. Surface adsorption of sulfonated poly(phenylene sulfone)/C14TAB mixtures and its correlation with foam film stability.

    PubMed

    Uhlig, Martin; Miller, Reinhard; Klitzing, Regine von

    2016-07-21

    Polyelectrolyte/surfactant mixtures of rigid monosulfonated poly(phenylene sulfone) (sPSO2-220) and tetradecyl trimethylammonium bromide (C14TAB) were investigated by surface tension, surface elasticity and foam film stability measurements. The results were compared to former measurements of polyelectrolyte/surfactant mixtures containing more flexible polyelectrolytes (PAMPS or PSS and C14TAB). For all polyelectrolyte/surfactant mixtures an increased surface adsorption in comparison to the pure surfactant was detected. Moreover, sPSO2-220/C14TAB mixtures showed a much higher surface activity and foam film stability than mixtures with more flexible polyelectrolytes. The results presented give insight into the surface adsorption and foam film formation of rigid polyelectrolyte/surfactant mixtures. Therefore, this study helps to understand the role of polyelectrolyte backbone rigidity in the formation and stabilization of foam films made from polyelectrolyte/surfactant mixtures.

  11. Electrochemical Windows of Sulfone-Based Electrolytes for High-Voltage Li-Ion Batteries

    SciTech Connect

    Shao, Nan; Sun, Xiao-Guang; Dai, Sheng; Jiang, Deen

    2011-01-01

    Further development of high-voltage lithium-ion batteries requires electrolytes with electrochemical windows greater than 5 V. Sulfone-based electrolytes are promising for such a purpose. Here we compute the electrochemical windows for experimentally tested sulfone electrolytes by different levels of theory in combination with various solvation models. The MP2 method combined with the polarizable continuum model is shown to be the most accurate method to predict oxidation potentials of sulfone-based electrolytes with mean deviation less than 0.29 V. Mulliken charge analysis shows that the oxidation happens on the sulfone group for ethylmethyl sulfone and tetramethylene sulfone, and on the ether group for ether functionalized sulfones. Large electrochemical windows of sulfone-based electrolytes are mainly contributed by the sulfone group in the molecules which helps lower the HOMO level. This study can help understand the voltage limits imposed by the sulfone-based electrolytes and aid in designing new electrolytes with greater electrochemical windows.

  12. Electrochemical windows of sulfone-based electrolytes for high-voltage Li-ion batteries.

    PubMed

    Shao, Nan; Sun, Xiao-Guang; Dai, Sheng; Jiang, De-en

    2011-10-27

    Further development of high-voltage lithium-ion batteries requires electrolytes with electrochemical windows greater than 5 V. Sulfone-based electrolytes are promising for such a purpose. Here we compute the electrochemical windows for experimentally tested sulfone electrolytes by different levels of theory in combination with various solvation models. The MP2 method combined with the polarizable continuum model is shown to be the most accurate method to predict oxidation potentials of sulfone-based electrolytes with mean deviation less than 0.29 V. Mulliken charge analysis shows that the oxidation happens on the sulfone group for ethylmethyl sulfone and tetramethylene sulfone, and on the ether group for ether functionalized sulfones. Large electrochemical windows of sulfone-based electrolytes are mainly contributed by the sulfone group in the molecules which helps lower the HOMO level. This study can help understand the voltage limits imposed by the sulfone-based electrolytes and aid in designing new electrolytes with greater electrochemical windows.

  13. Sulfonic Acid- and Lithium Sulfonate-Grafted Poly(Vinylidene Fluoride) Electrospun Mats As Ionic Liquid Host for Electrochromic Device and Lithium-Ion Battery.

    PubMed

    Zhou, Rui; Liu, Wanshuang; Leong, Yew Wei; Xu, Jianwei; Lu, Xuehong

    2015-08-05

    Electrospun polymer nanofibrous mats loaded with ionic liquids (ILs) are promising nonvolatile electrolytes with high ionic conductivity. The large cations of ILs are, however, difficult to diffuse into solid electrodes, making them unappealing for application in some electrochemical devices. To address this issue, a new strategy is used to introduce proton conduction into an IL-based electrolyte. Poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) copolymer is functionalized with sulfonic acid through covalent attachment of taurine. The sulfonic acid-grafted P(VDF-HFP) electrospun mats consist of interconnected nanofibers, leading to remarkable improvement in dimensional stability of the mats. IL-based polymer electrolytes are prepared by immersing the modified mats in 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM(+)BF4(-)). It is found that the SO3(-) groups can have Lewis acid-base interactions with the cations (BMIM(+)) of IL to promote the dissociation of ILs, and provide additional proton conduction, resulting in significantly improved ionic conductivity. Using this novel electrolyte, polyaniline-based electrochromic devices show higher transmittance contrast and faster switching behavior. Furthermore, the sulfonic acid-grafted P(VDF-HFP) electrospun mats can also be lithiated, giving additional lithium ion conduction for the IL-based electrolyte, with which Li/LiCoO2 batteries display enhanced C-rate performance.

  14. Synthesis and anticoagulant activity of bioisosteric sulfonic-Acid analogues of the antithrombin-binding pentasaccharide domain of heparin.

    PubMed

    Herczeg, Mihály; Lázár, László; Bereczky, Zsuzsanna; Kövér, Katalin E; Timári, István; Kappelmayer, János; Lipták, András; Antus, Sándor; Borbás, Anikó

    2012-08-20

    Two pentasaccharide sulfonic acids that were related to the antithrombin-binding domain of heparin were prepared, in which two or three primary sulfate esters were replaced by sodium-sulfonatomethyl moieties. The sulfonic-acid groups were formed on a monosaccharide level and the obtained carbohydrate sulfonic-acid esters were found to be excellent donors and acceptors in the glycosylation reactions. Throughout the synthesis, the hydroxy groups to be methylated were masked in the form of acetates and the hydroxy groups to be sulfated were masked with benzyl groups. The disulfonic-acid analogue was prepared in a [2+3] block synthesis by using a trisaccharide disulfonic acid as an acceptor and a glucuronide disaccharide as a donor. For the synthesis of the pentasaccharide trisulfonic acid, a more-efficient approach, which involved elongation of the trisaccharide acceptor with a non-oxidized precursor of the glucuronic acid followed by post-glycosidation oxidation at the tetrasaccharide level and a subsequent [1+4] coupling reaction, was elaborated. In vitro evaluation of the anticoagulant activity of these new sulfonic-acid derivatives revealed that the disulfonate analogue inhibited the blood-coagulation-proteinase factor Xa with outstanding efficacy; however, the introduction of the third sulfonic-acid moiety resulted in a notable decrease in the anti-Xa activity. The difference in the biological activity of the disulfonic- and trisulfonic-acid counterparts could be explained by the different conformation of their L-iduronic-acid residues.

  15. Controlling {beta}-amyloid oligomerization by the use of naphthalene sulfonates: trapping low molecular weight oligomeric species.

    PubMed

    Ferrão-Gonzales, Astria D; Robbs, Bruno K; Moreau, Vitor Hugo; Ferreira, Aricéle; Juliano, Luiz; Valente, Ana Paula; Almeida, Fabio C L; Silva, Jerson L; Foguel, Debora

    2005-10-14

    Aggregation of proteins and peptides has been shown to be responsible for several diseases known as amyloidoses, which include Alzheimer disease (AD), prion diseases, among several others. AD is a neurodegenerative disorder caused primarily by the aggregation of beta-amyloid peptide (Abeta). Here we describe the stabilization of small oligomers of Abeta by the use of sulfonated hydrophobic molecules such as AMNS (1-amino-5-naphthalene sulfonate); 1,8-ANS (1-anilinonaphthalene-8-sulfonate) and bis-ANS (4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonate). The experiments were performed with either Abeta-1-42 or with Abeta-13-23, a shorter version of Abeta that is still able to form amyloid fibrils in vitro and contains amino acid residues 16-20, previously shown to be essential to peptide-peptide interaction and fibril formation. All sulfonated molecules tested were able to prevent Abeta aggregation in a concentration dependent fashion in the following order of efficacy: 1,8-ANS < AMNS < bis-ANS. Size exclusion chromatography revealed that in the presence of bis-ANS, Abeta forms a heterogeneous population of low molecular weight species that proved to be toxic to cell cultures. Since the ANS compounds all have apolar rings and negative charges (sulfonate groups), both hydrophobic and electrostatic interactions may contribute to interpeptide contacts that lead to aggregation. We also performed NMR experiments to investigate the structure of Abeta-13-23 in SDS micelles and found features of an alpha-helix from Lys(16) to Phe(20). 1H TOCSY spectra of Abeta-13-23 in the presence of AMNS displayed a chemical-shift dispersion quite similar to that observed in SDS, which suggests that in the presence of AMNS this peptide might adopt a conformation similar to that reported in the presence of SDS. Taken together, our studies provide evidence for the crucial role of small oligomers and their stabilization by sulfonate hydrophobic compounds.

  16. Regioselective inversion of the hydroxyl group in D-ribo-phytosphingosine via a cyclic sulfate and bis-sulfonate intermediate.

    PubMed

    Lee, Yun Mi; Baek, Dong Jae; Lee, Seokwoo; Kim, Deukjoon; Kim, Sanghee

    2011-01-21

    The selective synthesis of D-xylo- and D-lyxo-phytosphingosines from commercially available D-ribo-phytosphingosine is described. Thermolysis of the N-carbonyl protected cyclic sulfate led to an inversion of configuration of the proximal hydroxyl group to give the xylo-isomer, whereas the corresponding bis-sulfonate resulted in an inversion of configuration of the distal hydroxyl group to give the lyxo-isomer. This study allowed the comparison between a cyclic sulfate and a bis-sulfonate in an intramolecular substitution reaction involving a carbonyl oxygen nucleophile.

  17. Room temperature synthesis of biodiesel using sulfonated graphitic carbon nitride

    EPA Science Inventory

    Sulfonation of graphitic carbon nitride (g-CN) affords a polar and strongly acidic catalyst, Sg-CN, which displays unprecedented reactivity and selectivity in biodiesel synthesis and esterification reactions at room temperature.

  18. Room temperature synthesis of biodiesel using sulfonated graphitic carbon nitride

    PubMed Central

    Baig, R. B. Nasir; Verma, Sanny; Nadagouda, Mallikarjuna N.; Varma, Rajender S.

    2016-01-01

    Sulfonation of graphitic carbon nitride (g-CN) affords a polar and strongly acidic catalyst, Sg-CN, which displays unprecedented reactivity and selectivity in biodiesel synthesis and esterification reactions at room temperature. PMID:27991593

  19. Room temperature synthesis of biodiesel using sulfonated graphitic carbon nitride.

    PubMed

    Baig, R B Nasir; Verma, Sanny; Nadagouda, Mallikarjuna N; Varma, Rajender S

    2016-12-19

    Sulfonation of graphitic carbon nitride (g-CN) affords a polar and strongly acidic catalyst, Sg-CN, which displays unprecedented reactivity and selectivity in biodiesel synthesis and esterification reactions at room temperature.

  20. Room temperature synthesis of biodiesel using sulfonated graphitic carbon nitride

    NASA Astrophysics Data System (ADS)

    Baig, R. B. Nasir; Verma, Sanny; Nadagouda, Mallikarjuna N.; Varma, Rajender S.

    2016-12-01

    Sulfonation of graphitic carbon nitride (g-CN) affords a polar and strongly acidic catalyst, Sg-CN, which displays unprecedented reactivity and selectivity in biodiesel synthesis and esterification reactions at room temperature.

  1. Affinity labelling enzymes with esters of aromatic sulfonic acids

    DOEpatents

    Wong, Show-Chu; Shaw, Elliott

    1977-01-01

    Novel esters of aromatic sulfonic acids are disclosed. The specific esters are nitrophenyl p- and m-amidinophenylmethanesulfonate. Also disclosed is a method for specific inactivation of the enzyme, thrombin, employing nitrophenyl p-amidinophenylmethanesulfonate.

  2. The Snail-Induced Sulfonation Pathway in Breast Cancer Metastasis

    DTIC Science & Technology

    2014-09-01

    AD_________________ Award Number: W81XWH-11-1-0494   TITLE: The Snail -Induced Sulfonation... Snail -Induced Sulfonation Pathway in Breast Cancer Metastasis 5b. GRANT NUMBER W81XWH-11-1-0494 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Dr...provided funding for a 3-year project that has resulted in fundamental new insights into how the transcription factor Snail can control gene

  3. Influence of water-soluble flavonoids, quercetin-5'-sulfonic acid sodium salt and morin-5'-sulfonic acid sodium salt, on antioxidant parameters in the subacute cadmium intoxication mouse model.

    PubMed

    Chlebda, Ewa; Magdalan, Jan; Merwid-Lad, Anna; Trocha, Małgorzata; Kopacz, Maria; Kuźniar, Anna; Nowak, Dorota; Szelag, Adam

    2010-03-01

    Water-soluble quercetin-5'-sulfonic acid sodium salt (NaQSA) and morin-5'-sulfonic acid sodium salt (NaMSA) could exert an antagonistic effect on cadmium intoxication. The aim of the study was to examine the influence of these substances on superoxide dismutase (SOD) and glutathione (GSH) levels in the mouse liver in the subacute cadmium intoxication model. NaQSA and NaMSA significantly counteracted cadmium-induced decreases in SOD and GSH levels. No significant differences in SOD and GSH levels between groups exposed to cadmium receiving NaQSA or/and NaMSA were observed.

  4. Crystal and molecular structure of alpha-iodo-beta-chlorovinyl phenyl sulfone and ,US -dibromovinyl phenyl sulfone

    SciTech Connect

    Bel'skii, V.K.; Shainyan, B.A.; Mirskova, A.N.

    1986-09-01

    The authors discuss rearrangement and isomerization procedures occurring in the bromination, iodination, and chlorination of the title sulfones and assess their crystal and molecular structure using NMR spectroscopy and x-ray diffraction.

  5. Development of peptidomimetics with a vinyl sulfone warhead as irreversible falcipain-2 inhibitors.

    PubMed

    Ettari, Roberta; Nizi, Emanuela; Di Francesco, Maria Emilia; Dude, Marie-Adrienne; Pradel, Gabriele; Vicík, Radim; Schirmeister, Tanja; Micale, Nicola; Grasso, Silvana; Zappalà, Maria

    2008-02-28

    This paper describes the synthesis of a new class of peptidomimetic cysteine protease inhibitors based on a 1,4-benzodiazepine scaffold and on an electrophilic vinyl sulfone moiety. The former was introduced internally to a peptide sequence that mimics the fragment D-Ser-Gly; the latter was built on the P1-P1' site and reacts as a classical "Michael acceptor", leading to an alkylated enzyme by irreversible addition of the thiol group of the active site cysteine. The introduction of the vinyl sulfone moiety has been accomplished by olefin cross-metathesis, a powerful tool for the formation of carbon-carbon double bonds. New compounds 2-3 have been proven to be potent and selective inhibitors of falcipain-2, a cysteine protease isolated from Plasmodium falciparum, displaying antiplasmodial activity.

  6. Proton Conductivity of Nafion/Ex-Situ Sulfonic Acid-Modified Stöber Silica Nanocomposite Membranes As a Function of Temperature, Silica Particles Size and Surface Modification.

    PubMed

    Muriithi, Beatrice; Loy, Douglas A

    2016-01-28

    The introduction of sulfonic acid modified silica in Nafion nanocomposite membranes is a good method of improving the Nafion performance at high temperature and low relative humidity. Sulfonic acid-modified silica is bifunctional, with silica phase expected to offer an improvement in membranes hydration while sulfonic groups enhance proton conductivity. However, as discussed in this paper, this may not always be the case. Proton conductivity enhancement of Nafion nanocomposite membranes is very dependent on silica particle size, sometimes depending on experimental conditions, and by surface modification. In this study, Sulfonated Preconcentrated Nafion Stober Silica composites (SPNSS) were prepared by modification of Stober silica particles with mercaptopropyltriethoxysilane, dispersing the particles into a preconcentrated solution of Nafion, then casting the membranes. The mercapto groups were oxidized to sulfonic acids by heating the membranes in 10 wt % hydrogen peroxide for 1 h. At 80 °C and 100% relative humidity, a 20%-30% enhancement of proton conductivity was only observed when sulfonic acid modified particle less than 50 nm in diameter were used. At 120 °C, and 100% humidity, proton conductivity increased by 22%-42% with sulfonated particles with small particles showing the greatest enhancement. At 120 °C and 50% humidity, the sulfonated particles are less efficient at keeping the membranes hydrated, and the composites underperform Nafion and silica-Nafion nanocomposite membranes.

  7. Proton Conductivity of Nafion/Ex-Situ Sulfonic Acid-Modified Stöber Silica Nanocomposite Membranes As a Function of Temperature, Silica Particles Size and Surface Modification

    PubMed Central

    Muriithi, Beatrice; Loy, Douglas A.

    2016-01-01

    The introduction of sulfonic acid modified silica in Nafion nanocomposite membranes is a good method of improving the Nafion performance at high temperature and low relative humidity. Sulfonic acid-modified silica is bifunctional, with silica phase expected to offer an improvement in membranes hydration while sulfonic groups enhance proton conductivity. However, as discussed in this paper, this may not always be the case. Proton conductivity enhancement of Nafion nanocomposite membranes is very dependent on silica particle size, sometimes depending on experimental conditions, and by surface modification. In this study, Sulfonated Preconcentrated Nafion Stober Silica composites (SPNSS) were prepared by modification of Stober silica particles with mercaptopropyltriethoxysilane, dispersing the particles into a preconcentrated solution of Nafion, then casting the membranes. The mercapto groups were oxidized to sulfonic acids by heating the membranes in 10 wt % hydrogen peroxide for 1 h. At 80 °C and 100% relative humidity, a 20%–30% enhancement of proton conductivity was only observed when sulfonic acid modified particle less than 50 nm in diameter were used. At 120 °C, and 100% humidity, proton conductivity increased by 22%–42% with sulfonated particles with small particles showing the greatest enhancement. At 120 °C and 50% humidity, the sulfonated particles are less efficient at keeping the membranes hydrated, and the composites underperform Nafion and silica-Nafion nanocomposite membranes. PMID:26828525

  8. Neuroendocrine effects of perfluorooctane sulfonate in rats.

    PubMed Central

    Austin, Maureen E; Kasturi, Badrinarayanan S; Barber, Matthew; Kannan, Kurunthachalam; MohanKumar, Puliyur S; MohanKumar, Sheba M J

    2003-01-01

    Perfluorooctane sulfonate (PFOS) is a degradation product of sulfonyl-based fluorochemicals that are used extensively in industrial and household applications. Humans and wildlife are exposed to this class of compounds from several sources. Toxicity tests in rodents have raised concerns about potential developmental, reproductive, and systemic effects of PFOS. However, the effect of PFOS on the neuroendocrine system has not been investigated thus far. In this study, adult female rats were injected intraperitoneally with 0, 1, or 10 mg PFOS/kg body weight (BW) for 2 weeks. Food and water intake, BW, and estrous cycles were monitored daily. At the end of treatment, PFOS levels in tissues were measured by high-performance liquid chromatography (HPLC) interfaced with electrospray mass spectrometry. Changes in brain monoamines were measured by HPLC with electrochemical detection, and serum corticosterone and leptin were monitored using radioimmunoassay. Treatment with PFOS produced a dose-dependent accumulation of this chemical in various body tissues, including the brain. PFOS exposure decreased food intake and BW in a dose-dependent manner. Treatment with PFOS affected estrous cyclicity and increased serum corticosterone levels while decreasing serum leptin concentrations. PFOS treatment also increased norepinephrine concentrations in the paraventricular nucleus of the hypothalamus. These results indicate that exposure to PFOS can affect the neuroendocrine system in rats. PMID:12948888

  9. Acute toxicity to goldfish of mixtures of chloramines, copper, and linear alkylate sulfonate

    SciTech Connect

    Tsai, C.F.; McKee, J.A.

    1980-01-01

    The toxicity to goldfish (Carassius auratus) of mixtures of chloramines, copper, and linear alkylate sulfonate (LAS) was studied by continuous-flow toxicity tests during an exposure period of 96 hours. The individual toxicities of these three chemicals are either additive or synergistic in mixtures, depending on the rate of toxic action of the individual chemical, the toxicity ratio of the chemicals in the mixtures, and the concentration of the mixtures.

  10. Prophylactic administration of non-organophosphate cholinesterase inhibitors before acute exposure to organophosphates: assessment using terbufos sulfone.

    PubMed

    Lorke, Dietrich E; Nurulain, Syed M; Hasan, Mohamed Y; Kuča, Kamil; Petroianu, Georg A

    2014-10-01

    Poisoning with organophosphorus compounds (OPCs) poses a serious threat worldwide. OPC-induced mortality can be significantly reduced by prophylactic administration of reversible acetylcholinesterase (AChE) inhibitors. The only American Food and Drug Administration (FDA)-approved substance for such pre-treatment (to soman exposure) is presently pyridostigmine, although its efficacy is controversial. In search for more efficacious and broad-spectrum alternatives, we have assessed in vivo the mortality-reducing efficacy of a group of five compounds with known AChE inhibitory activity (pyridostigmine, physostigmine, ranitidine, tacrine and K-27), when given in equitoxic dosage (25% of LD01 ) 30 min before exposure to the OPC terbufos sulfone. Protection was quantified in rats by determining the relative risk of death (RR) using Cox analysis, with RR = 1 for animals given only terbufos sulfone, but no pre-treatment. All tested AChE inhibitors reduced terbufos sulfone-induced mortality significantly (p ≤ 0.05) as compared with the non-treatment group (RR = 1: terbufos sulfone only). Best in vivo protection from terbufos sulfone-induced mortality was achieved, when K-27 was given before terbufos sulfone exposure (RR = 0.06), which was significantly (P ≤ 0.05) superior to the pre-treatment with all other tested compounds, for example tacrine (RR = 0.21), pyridostigmine (RR = 0.28), physostigmine (RR = 0.29) and ranitidine (RR = 0.33). The differences in efficacy between tacrine, pyridostigmine, physostigmine and ranitidine were not statistically significant. Prophylactic administration of an oxime (such as K-27) in case of imminent OPC exposure may be a viable option.

  11. One-Pot Parallel Synthesis of Alkyl Sulfides, Sulfoxides, and Sulfones.

    PubMed

    Bogolubsky, Andrey V; Moroz, Yurii S; Mykhailiuk, Pavel K; Ostapchuk, Eugeniy N; Rudnichenko, Alexander V; Dmytriv, Yurii V; Bondar, Anna N; Zaporozhets, Olga A; Pipko, Sergey E; Doroschuk, Roman A; Babichenko, Liudmyla N; Konovets, Anzhelika I; Tolmachev, Andrey

    2015-06-08

    A simple and cost-effective one-pot parallel synthesis approach to sulfides, sulfoxides, and sulfones from thiourea was elaborated. The method combines two procedures optimized to the parallel synthesis conditions: alkylation of thiourea with alkyl chlorides and mono or full oxidation of in situ generated sulfides with H2O2 or H2O2-(NH4)2MoO4. The experimental set up required commonly used lab equipment: conventional oven and ultrasonic bath; the work up includes filtration or extraction with chloroform. The method was evaluated on an 81 member library of drug-like sulfides, sulfoxides, and sulfones yielding the compounds on a 30-300 mg scale. A small-scale synthesis of 2-(benzhydrylsulfinyl)acetamide (modafinil) utilizing our approach resulted in similar efficiency to the published procedures.

  12. Interfacial assignment of branched-alkyl benzene sulfonates: A molecular simulation

    NASA Astrophysics Data System (ADS)

    Liu, Zi-Yu; Wei, Ning; Wang, Ce; Zhou, He; Zhang, Lei; Liao, Qi; Zhang, Lu

    2015-11-01

    A molecular dynamics simulation was conducted to analyze orientations of sodium branched-alkyl benzene sulfonates molecules at nonane/water interface, which is helpful to design optimal surfactant structures to achieve ultralow interfacial tension (IFT). Through the two dimensional density profiles, monolayer collapses are found when surfactant concentration continues to increase. Thus the precise scope of monolayer is certain and orientation can be analyzed. Based on the simulated results, we verdict the interfacial assignment of branched-alkyl benzene sulfonates at the oil-water interface, and discuss the effect of hydrophobic tail structure on surfactant assignment. Bigger hydrophobic size can slow the change rate of surfactant occupied area as steric hindrance, and surfactant meta hydrophobic tails have a stronger tendency to stretch to the oil phase below the collapsed concentration. Furthermore, an interfacial model with reference to collapse, increasing steric hindrance and charge repulsive force between interfacial surfactant molecules, responsible for effecting of surfactant concentration and structure has been supposed.

  13. A sulfonated poly (aryl ether ether ketone ketone) isomer: synthesis and DMFC performance

    SciTech Connect

    Kim, Yu Seung; Liu, Baijun; Hu, Wei; Jiang, Zhenhua; Robertson, Gilles; Guiver, Michael

    2009-01-01

    A sulfonated poly(aryl ether ether ketone ketone) (PEEKK) having a well-defined rigid homopolymer-like chemical structure was synthesized from a readily-prepared PEEKK post-sulfonation with concentrated sulfuric acid at room temperature within several hours. The polymer electrolyte membrane (PEM) cast from the resulting polymer exhibited an excellent combination of thermal resistance, oxidative and dimensional stability, low methanol fuel permeability and high proton conductivity. Furthermore, membrane electrode assemblies (MEAs) were successfully fabricated and good direct methanol fuel cell (DMFC) performance was observed. At 2 M MeOH feed, the current density at 0.5 V reached 165 mA/cm, which outperformed our reported analogues and eveluated Nafion membranes.

  14. Synthesis of a sulfonic acid mimetic of the sulfated Lewis A pentasaccharide.

    PubMed

    Jakab, Zsolt; Fekete, Anikó; Csávás, Magdolna; Borbás, Anikó; Lipták, András; Antus, Sándor

    2012-03-01

    The first sulfonic acid mimetic of the sulfated Lewis A pentasaccharide in which the natural L-fucose unit is replaced by a D-arabinose ring was synthesized. Formation of the sulfonic acid moiety at a pentasaccharide level could be successfully achieved by means of introduction of an acetylthio moiety into the terminal D-galactose residue and subsequent oxidation. The equatorial arrangement of the acetylthio group linked to C-3 of the galactose ring could be obtained by double nucleophilic substitutions; efficient formation of the gulo-triflate derivatives required low-power microwave (MW) activation. Oxidation of the acetylthio group was carried out using Oxone in the presence of acetic acid.

  15. Enzymatic treatment of sulfonated aromatic amines generated from reductive degradation of reactive azo dyes.

    PubMed

    Biswas, Mousumi Mani; Taylor, Keith E; Bewtra, Jatinder K; Biswas, Nihar

    2007-04-01

    Anaerobic degradation, an effective treatment process of textile industry effluent, generates sulfonated aromatic amines, which are carcinogenic, mutagenic, and resistant to microbial degradation. These aromatic amines can be effectively removed by oxidative polymerization catalyzed by peroxidase enzyme. The amines, generated in this study from the anaerobic reduction by zero-valent iron of two reactive azo dyes (Reactive Red 2 [RR2] and Reactive Black 5 [RB5]), were successfully removed (90%) by Arthromyces ramosus peroxidase (ARP). For better understanding of the process, enzymatic treatment of two model compounds, diphenylamine (DPA) and 2-amino-8-naphthol-3,6-disulfonic acid (ANDSA), were also studied. Diphenylamine has a similar diarylamine bond as RR2. The ANDSA has a similar structure as the dye reduction products. The secondary amine bond in DPA and RR2 were oxidized by ARP. Enzymatic reaction of sulfonated aromatic amines generated soluble colored compounds, which were removed by coagulant. Optimum reaction parameters were also determined.

  16. Mechanically and structurally robust sulfonated block copolymer membranes for water purification applications

    NASA Astrophysics Data System (ADS)

    Yeo, J.; Kim, S. Y.; Kim, S.; Ryu, D. Y.; Kim, T.-H.; Park, M. J.

    2012-06-01

    The effective removal of ionic pollutants from contaminated water using negatively charged nanofiltration membranes is demonstrated. Block copolymers comprising polystyrene (PS) and partially hydrogenated polyisoprene (hPI) were synthesized by varying chain architectures. A one step procedure of cross-linking (hPI blocks) and sulfonation reactions (PS chains) was then carried out, which was revealed as an effective method to enhance mechanical integrity of membranes while hydrophilic sulfonated chains remain intact. In particular, the control of chain architecture allows us to create a synergetic effect on optimizing charge densities of the membrane, water permeability, and mechanical integrity under water purification conditions. The best performing membrane can almost completely (>99%) reject various divalent cations and also show NO3- rejection > 85% and Na+ rejection > 87%. Well defined nanostructures (tens of nanometers) as well as the periodically arranged water domains (a few nanometers) within hydrophilic phases of the hydrated membranes were confirmed by in situ neutron scattering experiments.

  17. Colitis induced by sodium polystyrene sulfonate in sorbitol: A report of six cases.

    PubMed

    Jacob, Sheba S K; Parameswaran, Ashok; Parameswaran, Sarojini Ashok; Dhus, Ubal

    2016-03-01

    Drug-related injury has been noted in virtually all organ systems, and recognition of the patterns of injury associated with medication enables modification of treatment and reduces the morbidity associated with the side effects of drugs. With the large number of new drugs being developed, documentation of the morphology of the changes seen as an adverse effect becomes important to characterize the pattern of injury. The pathologist is often the first to identify these abnormalities and correlate them with a particular drug. Kayexalate or sodium polystyrene sulfonate (SPS), a linear polymer derived from polystyrene containing sulfonic acid and sulfonate functional groups is used to treat hyperkalemia. It is usually administered with an osmotic laxative sorbitol orally or as retention enema. This combination has been implicated in causing damage to different parts of the gastrointestinal (GI) tract especially the colon and causes an established pattern of injury, recognizable by the presence of characteristic crystals, is presented to create a greater awareness of the Kayexalate colitis. This entity should be included in the differential diagnosis of lower GI mucosal injury in a setting of uremia and hyperkalemia.

  18. New cation-exchange material based on a sulfonated 3,4-ethylenedioxythiophene monomer

    NASA Astrophysics Data System (ADS)

    Stéphan, O.; Schottland, P.; Le Gall, P.-Y.; Chevrot, C.

    1998-06-01

    The electrochemical oxidation, in aqueous medium, of a 3,4-ethylenedioxythiophene monomer functionalized by a sulfonate group exhibiting cation-exchange properties, allows the synthesis of a new type of water-soluble material. In order to synthesize in water, by oxidative electropolymerization, polymer films of controlled thickness containing attached sulfonate groups, we have investigated the polymerization of the functionalized monomer in the presence of the unsubstituted one without supporting electrolyte. Using an equimolar mixture (0.01 mol/l) of both monomers, copolymers exhibiting cation exchange abilities have been synthesized. As an example, th easy incorporation of hexaamine-ruthenium(III) into one of these copolymers is briefly reported. L'oxydation électrochimique en milieu aqueux d'un monomère de type 3,4- éthylènedioxythiophène fonctionnalisé par un groupement sulfonate permet d'envisager la synthèse d'un nouveau type de polymère hydrosoluble. Afin d'obtenir électrochimiquement en milieu aqueux, un film de polymère d'épaisseur contrôlée contenant des groupements sulfonates, nous avons evisagé de polymériser ce monomère en présence de son homologue non substitué. En partant d'un mélange équimolaire (0.01 mol/l) des deux monomères et en l'absence d'électrolyte support, nous avons synthétisé un matériau possédant des propriétés d'échange de cations. A titre d'exemple, nous présentons brièvement l'incorporation d'un complexe hexaaminé du ruthénium(III) dans un de ces copolymères.

  19. 2-Amino-6-methyl­pyridinium 4-methyl­benzene­sulfonate

    PubMed Central

    Babu, K. Syed Suresh; Dhavamurthy, M.; NizamMohideen, M.; Peramaiyan, G.; Mohan, R.

    2014-01-01

    In the asymmetric unit of the title salt, C6H9N2 +·C7H7O3S−, there are two independent 2-amino-6-methyl­pyridinium cations and two independent 4-methyl­benzene­sulfonate anions. Both cations are protonated at their pyridine N atoms and their geometries reveal amine–imine tautomerism. In the 4-methyl­benzene­sulfonate anions, the carboxyl­ate groups are twisted out of the benzene ring planes by 88.4 (1) and 86.2 (2)°. In the crystal, the sulfonate O atoms of an anion inter­act with the protonated N atoms and the 2-amino groups of a cation via a pair of N—H⋯O hydrogen bonds, forming an R 2 2(8) ring motif. These motifs are connected via N—H⋯O hydrogen bonds, forming chains running along the a-axis direction. Within the chains there are weak C—H⋯O hydrogen bonds present. In addition, aromatic π–π stacking inter­actions [centroid–centroid distances = 3.771 (2), 3.599 (2), 3.599 (2) and 3.497 (2) Å] involving neighbouring chains are also observed. PMID:24860395

  20. Major sulfonate transporter Soa1 in Saccharomyces cerevisiae and considerable substrate diversity in its fungal family

    PubMed Central

    Holt, Sylvester; Kankipati, Harish; De Graeve, Stijn; Van Zeebroeck, Griet; Foulquié-Moreno, Maria R.; Lindgreen, Stinus; Thevelein, Johan M.

    2017-01-01

    Sulfate is a well-established sulfur source for fungi; however, in soils sulfonates and sulfate esters, especially choline sulfate, are often much more prominent. Here we show that Saccharomyces cerevisiae YIL166C(SOA1) encodes an inorganic sulfur (sulfate, sulfite and thiosulfate) transporter that also catalyses sulfonate and choline sulfate uptake. Phylogenetic analysis of fungal SOA1 orthologues and expression of 20 members in the sul1Δ sul2Δ soa1Δ strain, which is deficient in inorganic and organic sulfur compound uptake, reveals that these transporters have diverse substrate preferences for sulfur compounds. We further show that SOA2, a S. cerevisiae SOA1 paralogue found in S. uvarum, S. eubayanus and S. arboricola is likely to be an evolutionary remnant of the uncharacterized open reading frames YOL163W and YOL162W. Our work highlights the importance of sulfonates and choline sulfate as sulfur sources in the natural environment of S. cerevisiae and other fungi by identifying fungal transporters for these compounds. PMID:28165463

  1. Genotoxicity of chryseno[4,5-bcd]thiophene and its sulfone derivative

    SciTech Connect

    Sinsheimer, J.E.; Hooberman, B.H.; Das, S.K.; Savla, P.M.; Ashe, A.J. III )

    1992-01-01

    The authors' recent syntheses of cryseno[4,5-bcd]thiophene together with its potential sulfone metabolite, chryseno[4,5-bcd]thiophene-4,4-dioxide, have made these compounds available for genotoxicity testing. Such toxicity testing is of interest as this thiophene is an isoster of the established carcinogen benzo[a]pyrene and is one of the thiaarenes which are potential environmental contaminants found in fossil fuels. Although the thiophene was less mutagenic than benzo[a]pyrene in Salmonella strains TA98 and TA100 after S9 activation, it exhibited in vivo chromosomal aberration activity equal to that of benzo[a]pyrene in the bone-marrow cells of mice. A reduced activity with Salmonella as well as in the bone-marrow cell assay for the sulfone does not support its role as the key active metabolic intermediate for the genotoxicity of the thiophene. Molecular orbital calculations would be consistent with the concept of activation through a diol-epoxide mechanism and offers an explanation for the reduced genotoxicity of the sulfone via this mechanism. These genotoxicity studies support the concern that sulfur isosters of established carcinogenic polycyclic aromatic hydrocarbons could themselves be toxic. 21 refs., 2 figs., 3 tabs.

  2. Production of Jatropha biodiesel fuel over sulfonic acid-based solid acids.

    PubMed

    Chen, Shih-Yuan; Lao-Ubol, Supranee; Mochizuki, Takehisa; Abe, Yohko; Toba, Makoto; Yoshimura, Yuji

    2014-04-01

    Sulfonic acid-functionalized platelet SBA-15 mesoporous silica with an acid capacity of 2.44mmol H(+) g-cat(-1) (shortly termed 15SA-SBA-15-p) was one-pot synthesized by co-condensation method. When applied as solid acid catalyst in synthesis of Jatropha biodiesel fuel (BDF), the 15SA-SBA-15-p catalyst showed higher activity and resistances to water and free fatty acid (FFA) than commercial sulfonic resins of Amberlyst-15 and SAC-13. For the continuous Jatropha BDF production, a steady 75-78wt% of fatty acid methyl ester (FAME) content was obtained over 15SA-SBA-15-p catalyst at 150°C for 75h, whereas the Amberlyst-15 and SAC-13 catalysts were quickly deactivated due to the decomposition of thermally unstable framework and serious leaching of sulfonic acids. More importantly, the quality, stability and cold flow characteristic of Jatropha BDF synthesized by 15SA-SBA-15-p catalyst were better than those synthesized by Amberlyst-15 and SAC-13 catalysts, making the blending with petro-diesel an easy task.

  3. Synergism between Airborne Singlet Oxygen and a Trisubstituted Olefin Sulfonate for the Inactivation of Bacteria

    PubMed Central

    2015-01-01

    The reactivity of a trisubstituted alkene surfactant (8-methylnon-7-ene-1 sulfonate, 1) to airborne singlet oxygen in a solution containing E. coli was examined. Surfactant 1 was prepared by a Strecker-type reaction of 9-bromo-2-methylnon-2-ene with sodium sulfite. Submicellar concentrations of 1 were used that reacted with singlet oxygen by an “ene” reaction to yield two hydroperoxides (7-hydroperoxy-8-methylnon-8-ene-1 sulfonate and (E)-8-hydroperoxy-8-methylnon-6-ene-1 sulfonate) in a 4:1 ratio. Exchanging the H2O solution for D2O where the lifetime of solution-phase singlet oxygen increases by 20-fold led to an ∼2-fold increase in the yield of hydroperoxides pointing to surface activity of singlet oxygen with the surfactant in a partially solvated state. In this airborne singlet oxygen reaction, E. coli inactivation was monitored in the presence and absence of 1 and by a LIVE/DEAD cell permeabilization assay. It was shown that the surfactant has low dark toxicity with respect to the bacteria, but in the presence of airborne singlet oxygen, it produces a synergistic enhancement of the bacterial inactivation. How the ene-derived surfactant hydroperoxides can provoke 1O2 toxicity and be of general utility is discussed. PMID:24611688

  4. Devopmental toxicity of perfluorooctane Sulfonate (PFOS) is ...

    EPA Pesticide Factsheets

    Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are members of a family of perfluorinated compounds. Both are environmentally persistent and found in the serum of wildlife and humans. PFOS and PFOA are developmentally toxic in laboratory rodents. Exposure to these chemicals in utero delays development and reduces postnatal survival and growth. Exposure to PFOS on the last 4 days of gestation in the rat is sufficient to reduce neonatal survival. PFOS and PFOA are weak agonists of PPARα. The reduced postnatal survival of neonatal mice exposed to PFOA was recently shown to depend on expression of PPARα. This study used PPARα knockout (KO) and 129S1/SvlmJ wild type (WT) mice to determine if PPARα expression is required for the developmental toxicity of PFOS. After mating overnight, the next day was designated gestation day (GD) 0. WT females were weighed and dosed orally from GD15-18 with 0.5% Tween-20, 4.5, 6.5, 8.5, or 10.5 mg PFOS/kg/day. KO females were dosed with water, 8.5 or 10.5 mg PFOS/kg/day. Dams and pups were observed daily and pups were weighed on postnatal day (PND) 1 and PND15. Eye opening was recorded from PND12-15. Dams and pups were killed on PND15, body and liver weights recorded, and serum collected. PFOS did not affect maternal weight gain or body or liver weights of the dams on PND15. Neonatal survival (PND1-15) was significantly reduced by PFOS in both WT and KO litters at all doses. WT and KO pup birth weight and wei

  5. Development and evaluation of sulfonated polysulfone membranes for the zinc-ferricyanide battery

    NASA Astrophysics Data System (ADS)

    Arnold, C., Jr.; Assink, R. A.

    1985-03-01

    The successful commercialization of the zinc/ferricyanide battery being developed by Lockheed depends in part on the availability of an inexpensive, chemically stable membrane. Other essential membrane properties include low area resistivity (1 - 5 (UC OMEGA) cm(2)) and a low rate of iron permeation (4 x 10(-5) millimoles Fe(cm (2))h). A cast membrane which contained one sulfonate group per repeating unit in th backbone exhibited good stability in the alkaline ferricyanide electrolyte and satisfied the membrane requirements cited above. In ongoing single cell cycling tests, average energy efficiencies of 77% were achieved over 85 charge discharge cycles with this membrane. If sulfonate polysulfone membranes can be mass produced by extrusion, they can be considered as viable candidates to replace the expensive perfluorsulfonate membranes that were used to demonstrate the technical feasibility of the zinc/ferricyanide battery. The feasibility of preparing composite sulfonated polysulfone membranes by impregnation of microporous PTFE was also demonstrated. The manufacture of composite membranes should be possible using chemical coating equipment.

  6. From thiol to sulfonic acid: modeling the oxidation pathway of protein thiols by hydrogen peroxide.

    PubMed

    van Bergen, Laura A H; Roos, Goedele; De Proft, Frank

    2014-08-07

    Hydrogen peroxide is a natural oxidant that can oxidize protein thiols (RSH) via sulfenic acid (RSOH) and sulfinic acid (RSO2H) to sulfonic acid (RSO3H). In this paper, we study the complete anionic and neutral oxidation pathway from thiol to sulfonic acid. Reaction barriers and reaction free energies for all three oxidation steps are computed, both for the isolated substrates and for the substrates in the presence of different model ligands (CH4, H2O, NH3) mimicking the enzymatic environment. We found for all three barriers that the anionic thiolate is more reactive than the neutral thiol. However, the assistance of the environment in the neutral pathway in a solvent-assisted proton-exchange (SAPE) mechanism can lower the reaction barrier noticeably. Polar ligands can decrease the reaction barriers, whereas apolar ligands do not influence the barrier heights. The same holds for the reaction energies: they decrease (become more negative) in the presence of polar ligands whereas apolar ligands do not have an influence. The consistently negative consecutive reaction energies for the oxidation in the anionic pathway when going from thiolate over sulfenic and sulfinic acid to sulfonic acid are in agreement with biological reversibility.

  7. Synergistic Effects of Mixing Sulfone and Ionic Liquid as Safe Electrolytes for Lithium Sulfur Batteries

    SciTech Connect

    Liao, Chen; Guo, Bingkun; Sun, Xiao-Guang; Dai, Sheng

    2014-11-26

    A strategy of mixing both an ionic liquid and sulfone is reported to give synergistic effects of reducing viscosity, increasing ionic conductivity, reducing polysulfide dissolution, and improving safety. The mixtures of ionic liquids and sulfones also show distinctly different physicochemical properties, including thermal properties and crystallization behavior. By using these electrolytes, lithium sulfur batteries assembled with lithium and mesoporous carbon composites show a reversible specific capacity of 1265 mAhg-1 (second cycle) by using 40% 1.0 M lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) in N-methyl-Npropylpyrrolidinium bis(trifluoromethylsulfonyl)imide with 60% 1.0 M LiTFSI in methylisopropylsulfone in the first cycle. This capacity is slightly lower than that obtained in pure 1.0 M LiTFSI as the sulfone electrolyte; however, it exhibits excellent cycling stability and remains as high as 655 mAhg1 even after 50 cycles. This strategy provides a method to alleviate polysulfide dissolution and redox shuttle phenomena, at the same time, with improved ionic conductivity.

  8. Synergistic Effects of Mixing Sulfone and Ionic Liquid as Safe Electrolytes for Lithium Sulfur Batteries

    DOE PAGES

    Liao, Chen; Guo, Bingkun; Sun, Xiao-Guang; ...

    2014-11-26

    A strategy of mixing both an ionic liquid and sulfone is reported to give synergistic effects of reducing viscosity, increasing ionic conductivity, reducing polysulfide dissolution, and improving safety. The mixtures of ionic liquids and sulfones also show distinctly different physicochemical properties, including thermal properties and crystallization behavior. By using these electrolytes, lithium sulfur batteries assembled with lithium and mesoporous carbon composites show a reversible specific capacity of 1265 mAhg-1 (second cycle) by using 40% 1.0 M lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) in N-methyl-Npropylpyrrolidinium bis(trifluoromethylsulfonyl)imide with 60% 1.0 M LiTFSI in methylisopropylsulfone in the first cycle. This capacity is slightly lower than thatmore » obtained in pure 1.0 M LiTFSI as the sulfone electrolyte; however, it exhibits excellent cycling stability and remains as high as 655 mAhg1 even after 50 cycles. This strategy provides a method to alleviate polysulfide dissolution and redox shuttle phenomena, at the same time, with improved ionic conductivity.« less

  9. HEPATIC GENE EXPRESSION PROFILING IN PERFLUOROHEXANE SULFONATE-EXPOSED WILD-TYPE AND PPARα-NULL MICE.

    EPA Science Inventory

    Perfluorohexane sulfonate (PFHxS) is one member of a group ofperfluoroakyl acids (PFAAs) presently recognized as widespread environmental contaminants. Like other PFAAs, PFHxS is also commonly found in human serum. Although PFHxS is presumed to be an activator of peroxisome proli...

  10. A FACILE ONE-POT SYNTHESIS OF β-KETO SULFONES FROM KETONES UNDER SOLVENT-FREE CONDITIONS

    EPA Science Inventory

    An easy solvent-free method is described for the conversion of ketones into β-keto sulfones in high yields that involves in situ generation of α-tosyloxyketones followed by nucleophilic substitution with sodium arene sulfinate in presence of tetra-butylammonium bromide at ...

  11. Analysis of metolachlor ethane sulfonic acid chirality in groundwater: A tool for dating groundwater movement in agricultural settings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chemical chirality of pesticides can be a useful tool for studying environmental processes. The chiral forms of metolachlor ethane sulfonic acid (MESA), an abundant metabolite of metolachlor, and metolachlor were examined over a 6 year period in groundwater and a groundwater-fed stream in a riparia...

  12. Asymmetric synthesis of allylic sulfonic acids: enantio- and regioselective iridium-catalyzed allylations of Na2SO3.

    PubMed

    Liu, Wei; Zhao, Xiao-ming; Zhang, Hong-bo; Zhang, Liang; Zhao, Ming-zhu

    2014-12-15

    An enantioselective allylation reaction of allylic carbonates with sodium sulfite (Na2 SO3 ) catalyzed by Ir complex was accomplished, providing allylic sulfonic acids in good to excellent yields with a high level of enantio- and regioselectivities. (R)-2-Phenyl-2-sulfoacetic acid, a key intermediate for the synthesis of Cefsulodin and Sulbenicillin, was synthesized as well.

  13. Sulfonic acid functionalized nano γ-Al2O3 catalyzed per-O-acetylated of carbohydrates.

    PubMed

    Wu, Liqiang; Yin, Zhikui

    2013-01-10

    A simple and clean synthesis of per-O-acetylation carbohydrate derivatives has been accomplished by treatment of sugars with a stoichiometric quantity of acetic anhydride under solvent-free conditions in the presence of sulfonic acid functionalized nano γ-Al(2)O(3) as an efficient and environmentally benign catalyst.

  14. Synthesis and characterization of sulfonated single-walled carbon nanotubes and their performance as solid acid catalyst

    SciTech Connect

    Yu Hao Jin Yuguang; Li Zhili; Peng Feng Wang Hongjuan

    2008-03-15

    Single-walled carbon nanotubes (SWCNTs) were treated with sulfuric acid at 300 deg. C to synthesize sulfonated SWCNTs (s-SWCNTs), which were characterized by electron microscopy, infrared, Raman and X-ray photoelectron spectroscopy, and thermo analysis. Compared with activated carbon, more sulfonic acid groups can be introduced onto the surfaces of SWCNTs. The high degree ({approx}20 wt%) of surface sulfonation led to hydrophilic sidewalls that allows the SWCNTs to be uniformly dispersed in water and organic solvents. The high surface acidity of s-SWCNTs was demonstrated by NH{sub 3} temperature-programmed desorption technique and tested by an acetic acid esterification reaction catalyzed by s-SWCNTs. The results show that the water-dispersive s-SWCNTs are an excellent solid acid catalyst and demonstrate the potential of SWCNTs in catalysis applications. - Graphical abstract: Sulfonated SWCNTs with 20 wt% -SO{sub 2}OH groups were prepared by a high-temperature H{sub 2}SO{sub 4} process, which transformed the hydrophobic surface of pristine SWCNTs to a hydrophilic surface and provided an excellent performance as solid acid catalyst.

  15. Uptake of cationic dyes by sulfonated coal: Sorption mechanism

    SciTech Connect

    Mittal, A.K.; Venkobachar, C.

    1996-04-01

    Mechanistic aspects of sorption of Rhodamine B and Methylene Blue by sulfonated coal have been investigated. The coal surface before and after sulfonation has been characterized with the help of cation-exchange capacity measurements and infrared (IR) spectroscopy. These studies indicate that sulfuric acid treatment not only incorporates a SO{sub 3}H group on the coal surface but also oxidizes both aliphatic and aromatic fractions. The IR spectroscopy has been extensively applied to locate the active sites on the surface of the sorbent and the participating functional groups of the dye molecule. Graphical models of the sorbate-sorbent interaction have been proposed. These models are applied to explain the variation in the uptake potential of these dyes by sulfonated coal.

  16. Surface Sulfonation of Polyvinyl Chloride by Plasma for Antithrombogenicity

    NASA Astrophysics Data System (ADS)

    Liu, Peng; Chen, Yashao

    2004-06-01

    To enhance the blood compatibility of Polyvinyl Chloride (PVC) film, the film was modified by SO2/O2 gas plasma treatment. The effect of surface sulfonation of PVC treated by various SO2/O2 gas plasma depended on the volume ratio O2/(SO2 + O2). When the volume ratio was 0.5, the effect of sulfonation was the best. Sulfonic acid groups were specifically and efficiently introduced onto the PVC surface, which was proved by x-ray photoelectron spectroscopy (XPS) and Attenuated Total Reflectance Fourier Transfer Infrared (ATR-FTIR) spectroscopy. The surface microstructure of modified PVC film was studied with scanning electron microscopy (SEM). The antithrombogenicity of the samples was determined by the activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT) and plasma recalcification time (PRT) tests and platelet adhesion experiment. The results indicated that the antithrombogenicity of modified PVC was improved remarkably.

  17. Immobilisation of fully sulfonated polyaniline on nanostructured calcium silicate.

    PubMed

    Borrmann, Thomas; Dominis, Anton; McFarlane, Andrew J; Johnston, James H; Richardson, Michael J; Kane-Maguire, Leon A P; Wallace, Gordon G

    2007-12-01

    Up to 7.4% (w/w) of the sulfonated polyaniline, poly(2-methoxyaniline-5-sulfonic acid) (PMAS) can be absorbed onto nanostructured calcium silicates. Spectroscopic and leaching studies on the novel PMAS-silicate nanocomposites obtained indicate that attachment of the PMAS occurs via electrostatic binding of PMAS sulfonate groups to Ca2+ sites on the silicates. The surface area and pore volume of the nanocomposites are comparable to those of pure silicate and increase the surface area of the PMAS polymer by several orders of magnitude. The PMAS emeraldine salt in the nanocomposites retains its chemical reactivity, being readily oxidised and reduced to its pernigraniline and leucoemeraldine forms, respectively. The conductivity of the composite is comparable to that of the pure PMAS, several orders of magnitude higher than that of dried nanostructured calcium silicate.

  18. [Inhibition of Staphylococcus epidermidis adhesion on titanium surface with bioactive water-soluble copolymers bearing sulfonate, phosphate or carboxylate functions].

    PubMed

    Poussard, L; Ouédraogo, C P; Pavon-Djavid, G; Migonney, V

    2012-04-01

    Implanted prostheses are sometimes subject to bacterial infections, which can threat their benefit rule on a long-term basis. Various methods are studied to fight against these infections. Among them, the grafting of bioactive polymers onto the prosthesis surface shows up as a promising way to the problem of infections. This work presents the influence of various water-soluble bioactive polymers on the inhibition of the Staphylococcus epidermidis adhesion on the titanium samples surfaces initially preadsorbed with various proteins. Whatever the studied protein is, it is shown that the bioactive polymer containing sulfonate functions generates an inhibition of the adhesion of Staphylococcus epidermidis. For a plasma preadsorption, the inhibition rate rises up to 68% when the concentration of sulfonate function is 2.5μmol/L. Titanium surfaces grafted with the bioactive polymer were also tested. We find an inhibitive activity of the adhesion close to that of the previous case. These preliminary results can point up a clinical interest in the fight against the medical devices infection, because they highlight a clear local effect of S. epidermidis adhesion inhibition. Copolymers containing other functional groups (phosphate or carboxylate) were dissolved in a bacterial suspension to monitor the influence of the composition on the adhesion inhibition. Their inhibition rates are not significantly lower than those of pNaSS homopolymers, as much as the sulfonate function proportion remains higher than 50%. Thus, the sulfonate function is the main responsible for the inhibition of the S. epidermidis adhesion.

  19. Perfluorooctane sulfonate (PFOS) induced embryotoxicity and disruption of cardiogenesis.

    PubMed

    Cheng, Wei; Yu, Zhuo; Feng, Lixin; Wang, Yan

    2013-08-01

    Prenatal exposure to perfluorooctane sulfonate (PFOS) is correlated with birth defects and adverse health effects. However, the mechanisms remain largely unknown. In current study, the embryonic stem cell test (EST) was performed to evaluate the embryotoxicity of PFOS, and embryonic stem cells (ESCs)-derived cardiomyocytes were used as a model of the early stages of heart development to determine the developmental toxicity of PFOS. One validated endpoint and three molecular endpoints were observed to ensure accurate evaluation of toxicity. According to the criteria of the EST, PFOS was classified as weak embryotoxic. In addition, a cascade of genes related to normal cardiac development was examined at three different time points to monitor cardiogenesis. We found that PFOS significantly interfered with gene expression during cardiogenesis, especially on Nkx2.5 and Myl4. Further, PFOS reduced ATP production in ESCs-derived cardiomyocytes, together with PFOS induced apoptosis, could explain the reduction in beating ability. PFOS-induced reactive oxygen species (ROS) accumulated within cells, which was accompanied by an interfering expression of apoptosis-related genes, ultimately leading to apoptosis. In conclusion, PFOS altered the expression of crucial genes, reduced ATP production, induced ROS, and stimulated apoptosis during the early stages of cardiogenesis; these effects may result in poor developmental outcomes.

  20. Intestinal Necrosis due to Sodium Polystyrene Sulfonate (Kayexalate) in Sorbitol

    PubMed Central

    McGowan, C. E.; Saha, S.; Chu, G.; Resnick, M. B.; Moss, S. F.

    2013-01-01

    Background Sodium polystyrene sulfonate (SPS, Kayexalate) has been implicated in the development of intestinal necrosis. Sorbitol, added as a cathartic agent, may be primarily responsible. Previous studies have documented bowel necrosis primarily in postoperative, dialysis, and transplant patients. We sought to identify additional clinical characteristics among patients with probable SPS-induced intestinal necrosis. Methods Rhode Island Hospital surgical pathology records were reviewed to identify all gastrointestinal specimens reported as containing SPS crystals from December 1998 to June 2007. Patient demographics, medical comorbidities, and hospital courses of histologically verified cases of intestinal necrosis were extracted from the medical records. Results Twenty-nine patients with reports of SPS crystals were identified. Nine cases were excluded as incidental findings with normal mucosa. Nine patients were excluded as their symptoms began before SPS administration or because an alternate etiology for bowel ischemia was identified. Eleven patients had confirmed intestinal necrosis and a temporal relationship with SPS administration suggestive of SPS-induced necrosis. Only 2 patients were postoperative, and only 4 had end-stage renal disease (ESRD). All patients had documented hyperkalemia, received oral SPS, and developed symptoms of intestinal injury between 3 hours and 11 days after SPS administration. Four patients died. Conclusion Intestinal ischemia is a recognized risk of SPS in sorbitol. Our series highlights that patients may be susceptible even in the absence of ESRD, surgical intervention, or significant comorbidity. PMID:19373153

  1. Viscoelastic and Transport Properties of Sulfonated PS-PIB-PS Block Copolymers

    DTIC Science & Technology

    2001-05-01

    000 1200 Time (min) Figure 13. IR intensity vs. time for ethanol through three sulfonated P5-PIB- PS membranes. Figure 14 shows a comparison of four ...sulfonated PS -PIB- PS membrane. Table 1 shows a comparison of the equilibrium sorbtion values for the four alcohols in the sulfonated PS -PIB- PS . Table 1...Army Research Laboratory Aberdeen Proving Ground, MD 21005-5069 ARL-TR-2482 May2001 Viscoelastic and Transport Properties of Sulfonated PS -PIB- PS

  2. Sulfur and Hydrogen Isotope Anomalies in Meteorite Sulfonic Acids

    NASA Technical Reports Server (NTRS)

    Cooper, George W.; Thiemens, Mark H.; Jackson, Teresa L.; Chang, Sherwood

    1997-01-01

    Intramolecular carbon, hydrogen, and sulfur isotope ratios were measured on a homologous series of organic sulfonic acids discovered in the Murchison meteorite. Mass-independent sulfur isotope fractionations were observed along with high deuterium/hydrogen ratios. The deuterium enrichments indicate formation of the hydrocarbon portion of these compounds in a low-temperature environment that is consistent with that of interstellar clouds. Sulfur-33 enrichments observed in methanesulfonic acid could have resulted from gas-phase ultraviolet irradiation of a precursor, carbon disulfide. The source of the sulfonic acid precursors may have been the reactive interstellar molecule carbon monosulfide.

  3. 40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl...

  4. 40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl...

  5. 40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl...

  6. 40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl...

  7. 40 CFR 721.9595 - Alkyl benzene sulfonic acids and alkyl sulfates, amine salts (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkyl benzene sulfonic acids and alkyl... Significant New Uses for Specific Chemical Substances § 721.9595 Alkyl benzene sulfonic acids and alkyl...) The chemical substances identified generically as alkyl benzene sulfonic acids and alkyl...

  8. 40 CFR 721.10633 - Aromatic sulfonic acid amino azo dye salts (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Aromatic sulfonic acid amino azo dye... Specific Chemical Substances § 721.10633 Aromatic sulfonic acid amino azo dye salts (generic). (a) Chemical... as aromatic sulfonic acid amino azo dye salts (PMN P-12-276) is subject to reporting under...

  9. 40 CFR 721.10474 - Substituted amino ethane sulfonic acid salt (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted amino ethane sulfonic acid... Specific Chemical Substances § 721.10474 Substituted amino ethane sulfonic acid salt (generic). (a... generically as substituted amino ethane sulfonic acid salt (PMN P-04-107) is subject to reporting under...

  10. 40 CFR 721.10633 - Aromatic sulfonic acid amino azo dye salts (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Aromatic sulfonic acid amino azo dye... Specific Chemical Substances § 721.10633 Aromatic sulfonic acid amino azo dye salts (generic). (a) Chemical... as aromatic sulfonic acid amino azo dye salts (PMN P-12-276) is subject to reporting under...

  11. 40 CFR 721.10474 - Substituted amino ethane sulfonic acid salt (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted amino ethane sulfonic acid... Specific Chemical Substances § 721.10474 Substituted amino ethane sulfonic acid salt (generic). (a... generically as substituted amino ethane sulfonic acid salt (PMN P-04-107) is subject to reporting under...

  12. 40 CFR 721.9674 - Sulfonated-copper phthalocyanine salt of a triarylmethane dye (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sulfonated-copper phthalocyanine salt... Significant New Uses for Specific Chemical Substances § 721.9674 Sulfonated-copper phthalocyanine salt of a... chemical substance identified generically as sulfonated-copper phthalocyanine salt of a triarylmethane...

  13. 40 CFR 721.9674 - Sulfonated-copper phthalocyanine salt of a triarylmethane dye (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Sulfonated-copper phthalocyanine salt... Significant New Uses for Specific Chemical Substances § 721.9674 Sulfonated-copper phthalocyanine salt of a... chemical substance identified generically as sulfonated-copper phthalocyanine salt of a triarylmethane...

  14. 40 CFR 721.9597 - Salt of a substituted sulfonated aryl azo compound (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Salt of a substituted sulfonated aryl... New Uses for Specific Chemical Substances § 721.9597 Salt of a substituted sulfonated aryl azo... substance identified generically as salt of a substituted sulfonated aryl azo compound (PMN P-00-0094)...

  15. 40 CFR 721.2565 - Alkylated sulfonated diphenyl oxide, alkali and amine salts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkylated sulfonated diphenyl oxide... New Uses for Specific Chemical Substances § 721.2565 Alkylated sulfonated diphenyl oxide, alkali and... substances identified as alkylated sulfonated diphenyl oxide, alkali salt (PMN P-93-352) and...

  16. 40 CFR 721.2565 - Alkylated sulfonated diphenyl oxide, alkali and amine salts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkylated sulfonated diphenyl oxide... New Uses for Specific Chemical Substances § 721.2565 Alkylated sulfonated diphenyl oxide, alkali and... substances identified as alkylated sulfonated diphenyl oxide, alkali salt (PMN P-93-352) and...

  17. 40 CFR 721.9597 - Salt of a substituted sulfonated aryl azo compound (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Salt of a substituted sulfonated aryl... New Uses for Specific Chemical Substances § 721.9597 Salt of a substituted sulfonated aryl azo... substance identified generically as salt of a substituted sulfonated aryl azo compound (PMN P-00-0094)...

  18. 40 CFR 721.644 - Amines, C12-14-tert-alkyl, sulfonates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Amines, C12-14-tert-alkyl, sulfonates... Substances § 721.644 Amines, C12-14-tert-alkyl, sulfonates. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as amines, C12-14-tert-alkyl, sulfonates...

  19. 40 CFR 721.644 - Amines, C12-14-tert-alkyl, sulfonates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amines, C12-14-tert-alkyl, sulfonates... Substances § 721.644 Amines, C12-14-tert-alkyl, sulfonates. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as amines, C12-14-tert-alkyl, sulfonates...

  20. 40 CFR 721.5450 - α-Olefin sulfonate, sodium salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false α-Olefin sulfonate, sodium salt. 721... Substances § 721.5450 α-Olefin sulfonate, sodium salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as α-olefin sulfonate, sodium...

  1. 78 FR 62443 - Perfluoroalkyl Sulfonates and Long-Chain Perfluoroalkyl Carboxylate Chemical Substances; Final...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-22

    ... AGENCY 40 CFR Parts 9 and 721 RIN 2070-AJ95 Perfluoroalkyl Sulfonates and Long-Chain Perfluoroalkyl... new use rule (SNUR) for perfluoroalkyl sulfonate (PFAS) chemical substances to add PFAS chemical... general category of perfluorinated sulfonate chemical substances of any chain ] length. The PFAS...

  2. 40 CFR 721.5450 - α-Olefin sulfonate, sodium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false α-Olefin sulfonate, sodium salt. 721... Substances § 721.5450 α-Olefin sulfonate, sodium salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as α-olefin sulfonate, sodium...

  3. 40 CFR 721.10437 - Sulfonic acid, linear xylene alkylate, mono, sodium salts (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Sulfonic acid, linear xylene alkylate... Significant New Uses for Specific Chemical Substances § 721.10437 Sulfonic acid, linear xylene alkylate, mono... chemical substances identified generically as sulfonic acid, linear xylene alkylate, mono, sodium...

  4. 40 CFR 721.10437 - Sulfonic acid, linear xylene alkylate, mono, sodium salts (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Sulfonic acid, linear xylene alkylate... Significant New Uses for Specific Chemical Substances § 721.10437 Sulfonic acid, linear xylene alkylate, mono... chemical substances identified generically as sulfonic acid, linear xylene alkylate, mono, sodium...

  5. 40 CFR 721.9620 - Aromatic sulfonic acid compound with amine.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Aromatic sulfonic acid compound with... Specific Chemical Substances § 721.9620 Aromatic sulfonic acid compound with amine. (a) Chemical substance... aromatic sulfonic acid compound with amine (PMN P-93-832) is subject to reporting under this section...

  6. 40 CFR 721.9620 - Aromatic sulfonic acid compound with amine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Aromatic sulfonic acid compound with... Specific Chemical Substances § 721.9620 Aromatic sulfonic acid compound with amine. (a) Chemical substance... aromatic sulfonic acid compound with amine (PMN P-93-832) is subject to reporting under this section...

  7. 40 CFR 721.9620 - Aromatic sulfonic acid compound with amine.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Aromatic sulfonic acid compound with... Specific Chemical Substances § 721.9620 Aromatic sulfonic acid compound with amine. (a) Chemical substance... aromatic sulfonic acid compound with amine (PMN P-93-832) is subject to reporting under this section...

  8. 40 CFR 721.9620 - Aromatic sulfonic acid compound with amine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aromatic sulfonic acid compound with... Specific Chemical Substances § 721.9620 Aromatic sulfonic acid compound with amine. (a) Chemical substance... aromatic sulfonic acid compound with amine (PMN P-93-832) is subject to reporting under this section...

  9. 40 CFR 721.9620 - Aromatic sulfonic acid compound with amine.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Aromatic sulfonic acid compound with... Specific Chemical Substances § 721.9620 Aromatic sulfonic acid compound with amine. (a) Chemical substance... aromatic sulfonic acid compound with amine (PMN P-93-832) is subject to reporting under this section...

  10. 40 CFR 721.5450 - α-Olefin sulfonate, sodium salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false α-Olefin sulfonate, sodium salt. 721... Substances § 721.5450 α-Olefin sulfonate, sodium salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as α-olefin sulfonate, sodium...

  11. 40 CFR 721.5450 - α-Olefin sulfonate, sodium salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false α-Olefin sulfonate, sodium salt. 721... Substances § 721.5450 α-Olefin sulfonate, sodium salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as α-olefin sulfonate, sodium...

  12. 40 CFR 721.5450 - α-Olefin sulfonate, sodium salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false α-Olefin sulfonate, sodium salt. 721... Substances § 721.5450 α-Olefin sulfonate, sodium salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as α-olefin sulfonate, sodium...

  13. Chemical Agent Performance of Sulfonated Ionomeric Membranes for Chem/Bio Applications

    DTIC Science & Technology

    2008-12-01

    Polyisobutylene ( PIB ) Chemically Modified IB Sulfonic Acid Counter-ion (Ba, Mg, Ca, Zn, Cs)Block Copolymer Morphology Sulfonic acid...Mauritz, K., 2000: Diffusion of Alcohols Through Sulfonated PS/ PIB /PS Block Copolymers Using FTIR-ATR Spectroscopy, Polymer Materials: Engineering

  14. 40 CFR 721.10564 - Mixed amino diaryl sulfone isomers (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Mixed amino diaryl sulfone isomers... Specific Chemical Substances § 721.10564 Mixed amino diaryl sulfone isomers (generic). (a) Chemical... as mixed amino diaryl sulfone isomers (PMN P-08-39) is subject to reporting under this section...

  15. 40 CFR 721.10564 - Mixed amino diaryl sulfone isomers (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Mixed amino diaryl sulfone isomers... Specific Chemical Substances § 721.10564 Mixed amino diaryl sulfone isomers (generic). (a) Chemical... as mixed amino diaryl sulfone isomers (PMN P-08-39) is subject to reporting under this section...

  16. 40 CFR 721.9674 - Sulfonated-copper phthalocyanine salt of a triarylmethane dye (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Sulfonated-copper phthalocyanine salt... Significant New Uses for Specific Chemical Substances § 721.9674 Sulfonated-copper phthalocyanine salt of a... chemical substance identified generically as sulfonated-copper phthalocyanine salt of a triarylmethane...

  17. 40 CFR 721.9674 - Sulfonated-copper phthalocyanine salt of a triarylmethane dye (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Sulfonated-copper phthalocyanine salt... Significant New Uses for Specific Chemical Substances § 721.9674 Sulfonated-copper phthalocyanine salt of a... chemical substance identified generically as sulfonated-copper phthalocyanine salt of a triarylmethane...

  18. 40 CFR 721.9674 - Sulfonated-copper phthalocyanine salt of a triarylmethane dye (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Sulfonated-copper phthalocyanine salt... Significant New Uses for Specific Chemical Substances § 721.9674 Sulfonated-copper phthalocyanine salt of a... chemical substance identified generically as sulfonated-copper phthalocyanine salt of a triarylmethane...

  19. 40 CFR 721.10487 - Alkylbenzenes sulfonic acids, metal salts (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Alkylbenzenes sulfonic acids, metal... Specific Chemical Substances § 721.10487 Alkylbenzenes sulfonic acids, metal salts (generic). (a) Chemical... as alkylbenzenes sulfonic acids, metal salts (PMNs P-04-599, P-04-600, P-04-605, and P-04-606)...

  20. 40 CFR 721.10487 - Alkylbenzenes sulfonic acids, metal salts (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkylbenzenes sulfonic acids, metal... Specific Chemical Substances § 721.10487 Alkylbenzenes sulfonic acids, metal salts (generic). (a) Chemical... as alkylbenzenes sulfonic acids, metal salts (PMNs P-04-599, P-04-600, P-04-605, and P-04-606)...

  1. Reaction kinetics of free fatty acids esterification in palm fatty acid distillate using coconut shell biochar sulfonated catalyst

    NASA Astrophysics Data System (ADS)

    Hidayat, Arif; Rochmadi, Wijaya, Karna; Budiman, Arief

    2015-12-01

    Recently, a new strategy of preparing novel carbon-based solid acids has been developed. In this research, the esterification reactions of Palm Fatty Acid Distillate (PFAD) with methanol, using coconut shell biochar sulfonated catalyst from biomass wastes as catalyst, were studied. In this study, the coconut shell biochar sulfonated catalysts were synthesized by sulfonating the coconut shell biochar using concentrated H2SO4. The kinetics of free fatty acid (FFA) esterification in PFAD using a coconut shell biochar sulfonated catalyst was also studied. The effects of the mass ratio of catalyst to oil (1-10%), the molar ratio of methanol to oil (6:1-12:1), and the reaction temperature (40-60°C) were studied for the conversion of PFAD to optimize the reaction conditions. The results showed that the optimal conditions were an methanol to PFAD molar ratio of 12:1, the amount of catalyst of 10%w, and reaction temperature of 60°C. The proposed kinetic model shows a reversible second order reaction and represents all the experimental data satisfactorily, providing deeper insight into the kinetics of the reaction.

  2. Effects of ammonioalkyl sulfonate internal salts on electrokinetic micropump performance and reversed-phase high-performance liquid chromatographic separations.

    PubMed

    Reichmuth, David S; Kirby, Brian J

    2003-09-26

    Ammonioalkyl sulfonate internal salts are explored owing to their potential for improving electrokinetic pumps used to perform miniaturized HPLC separations. The internal salts investigated can be added at high molarity since they are net-neutral, and furthermore show potential for increasing electroosmotic pumping owing to their large positive dielectric increment. Streaming potential measurements of buffered aqueous systems with varying concentrations of ammonioalkyl sulfonate internal salts have been used to measure these dielectric increments, which increase with the length of the alkyl linker. Due to their positive dielectric increments and their decremental effect on solution conductivity, all of the measured species are predicted to improve the pressure generation (up to 85%) and efficiency performance (up to 140%) of electrokinetic pumps when added at 1 M concentration. RP-HPLC separations with an ammonioalkyl sulfonate (TMAPS) have been performed and indicate that separation performance is essentially unaffected by these species. These results indicate the potential for a variety of ammonioalkyl sulfonates to be used to improve electrokinetic pump performance for miniaturized HPLC.

  3. Estimated pKa values for the environmentally relevant C1 through C8 perfluorinated sulfonic acid isomers.

    PubMed

    Rayne, Sierra; Forest, Kaya

    2016-10-14

    In order to estimate isomer-specific acidity constants (pKa) for the perfluorinated sulfonic acid (PFSA) environmental contaminants, the parameterization method 6 (PM6) pKa prediction method was extensively validated against a wide range of carbon oxyacids and related sulfonic/sulfinic acids. Excellent pKa prediction performance was observed for the carbon oxyacids using the PM6 method, but this approach was found to have a severe positive bias for sulfonic/sulfinic acids. To overcome this obstacle, a correlation was developed between non-adjusted PM6 pKa values and the corresponding experimentally obtained/estimated acidity constants for a range of representative alkyl, aryl and halogen-substituted sulfonic acids. Application of this correction to the PM6 values allows for extension of this computational method to a new acid functional group. When used to estimate isomer-specific pKa values for the C1 through C8 PFSAs, the modified PM6 approach suggests an adjusted pKa range from -5.3 to -9.0, indicating that all members of this class of well-known environmental contaminants will be effectively completely dissociated in aquatic systems.

  4. Homolytic C-O cleavage in phosphates and sulfonates.

    PubMed

    Ding, Lanlan; Zheng, Wenrui; Wang, Yingxing

    2015-04-09

    The C-O homolytic bond dissociation enthalpies(BDEs) were calculated by high-level ab initio including G4, G3B3, G3, CBS-QB3 and a series of density function theory (DFT) methods. It is found that the wB97 method gave the most reliable C-O BDEs and the root-mean-square deviation (RMSD) is 7.6 kJ/mol. Therefore, the C(sp(2))-O BDE predictions and the substituent effects of alkenyl phosphates/sulfonates and aryl phosphates/sulfonates were investigated in detail by using the wB97 method. Interestingly, there exist different substituent effects in α- and β-substituted alkenyl phosphates/sulfonates. Excellent linear relationships between the C-O BDEs of β-substituted alkenyl phosphates/sulfonates with substituent constant σp(+) were found. In addition, the NBO analysis further disclosed the essence of the substituent effects on C-O BDEs.

  5. Complexes of poly-N-vinylpyrrolidone with sulfonated tetraphenylporphins

    SciTech Connect

    Kulvelis, Yu. V. Lebedev, V. T.; Toeroek, Gy.; Klyubin, V. V.

    2007-05-15

    The interaction of sulfonated tetraphenylporphins H{sub 2}TPPS{sub 4}(HCl){sub 2} and in CuTPPS{sub 4} with poly-N-vinylpyrrolidone (PVP) is studied using small-angle neutron scattering, dynamic light scattering, visible spectrophotometry, and viscometry. It is shown that porphyrin molecules form complexes with PVP, thus charging the polymeric chain.

  6. 21 CFR 177.2500 - Polyphenylene sulfone resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ....2500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Components of Articles Intended for Repeated Use § 177.2500 Polyphenylene sulfone resins. The polyphenylene... articles or components of articles intended for repeated use in contact with food, subject to...

  7. 21 CFR 177.2500 - Polyphenylene sulfone resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ....2500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Components of Articles Intended for Repeated Use § 177.2500 Polyphenylene sulfone resins. The polyphenylene... articles or components of articles intended for repeated use in contact with food, subject to...

  8. 21 CFR 177.2500 - Polyphenylene sulfone resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ....2500 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Components of Articles Intended for Repeated Use § 177.2500 Polyphenylene sulfone resins. The polyphenylene... articles or components of articles intended for repeated use in contact with food, subject to...

  9. 21 CFR 177.2210 - Ethylene polymer, chloro-sulfonated.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ethylene polymer, chloro-sulfonated. 177.2210... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use Only as Components of Articles Intended for Repeated Use § 177.2210 Ethylene polymer,...

  10. 21 CFR 177.2210 - Ethylene polymer, chloro-sulfonated.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ethylene polymer, chloro-sulfonated. 177.2210... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use Only as Components of Articles Intended for Repeated Use § 177.2210 Ethylene polymer,...

  11. 21 CFR 177.2210 - Ethylene polymer, chloro-sulfonated.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ethylene polymer, chloro-sulfonated. 177.2210... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use Only as Components of Articles Intended for Repeated Use § 177.2210 Ethylene polymer,...

  12. 21 CFR 177.2210 - Ethylene polymer, chloro-sulfonated.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene polymer, chloro-sulfonated. 177.2210... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use Only as Components of Articles Intended for Repeated Use § 177.2210 Ethylene polymer,...

  13. 21 CFR 173.395 - Trifluoromethane sulfonic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... has the empirical formula CF3SO3H (CAS Reg. No. 1493-13-6). The catalyst (Trifluoromethane sulfonic... catalyst meets the following specifications: Appearance, Clear liquid. Color, Colorless to amber... esterification reaction is quenched with steam and water and the catalyst is removed with the aqueous...

  14. 21 CFR 173.395 - Trifluoromethane sulfonic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... CF3SO3H (CAS Reg. No. 1493-13-6). The catalyst (Trifluoromethane sulfonic acid) may safely be used in the... chapter) in accordance with the following conditions: (a) The catalyst meets the following specifications... steam and water and the catalyst is removed with the aqueous phase. Final traces of catalyst are...

  15. 21 CFR 173.395 - Trifluoromethane sulfonic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... sulfonic acid has the empirical formula CF3SO3H (CAS Reg. No. 1493-13-6). The catalyst (Trifluoromethane... catalyst meets the following specifications: Appearance, Clear liquid. Color, Colorless to amber... esterification reaction is quenched with steam and water and the catalyst is removed with the aqueous...

  16. 21 CFR 173.395 - Trifluoromethane sulfonic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... sulfonic acid has the empirical formula CF3SO3H (CAS Reg. No. 1493-13-6). The catalyst (Trifluoromethane... catalyst meets the following specifications: Appearance, Clear liquid. Color, Colorless to amber... esterification reaction is quenched with steam and water and the catalyst is removed with the aqueous...

  17. 21 CFR 173.395 - Trifluoromethane sulfonic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... sulfonic acid has the empirical formula CF3SO3H (CAS Reg. No. 1493-13-6). The catalyst (Trifluoromethane... catalyst meets the following specifications: Appearance, Clear liquid. Color, Colorless to amber... esterification reaction is quenched with steam and water and the catalyst is removed with the aqueous...

  18. In silico approach to investigating the adsorption mechanisms of short chain perfluorinated sulfonic acids and perfluorooctane sulfonic acid on hydrated hematite surface.

    PubMed

    Feng, Hongru; Lin, Yuan; Sun, Yuzhen; Cao, Huiming; Fu, Jianjie; Gao, Ke; Zhang, Aiqian

    2017-05-01

    Short chain perfluorinated sulfonic acids (PFSAs) that were introduced as alternatives for perfluorooctane sulfonic acid (PFOS) have been widely produced and used. However, few studies have investigated the environmental process of short chain PFSAs, and the related adsorption mechanisms still need to be uncovered. The water-oxide interface is one of the major environmental interfaces that plays an important role in affecting the adsorption behaviour and transport potential of the environmental pollutant. In this study, we performed molecular dynamics simulations and quantum chemistry calculations to investigate the adsorption mechanisms of five PFSAs and their adsorption on hydrated hematite surface as well. Different to the vertical configuration reported for PFOS on titanium oxide, all PFSAs share the same adsorption configuration as the long carbon chains parallel to the surface. The formation of hydrogen bonds between F and inter-surface H helps to stabilize the unique configuration. As a result, the sorption capacity increases with increasing C-F chain length. Moreover, both calculated adsorption energy and partial density of states (PDOS) analysis demonstrate a PFSAs adsorption mechanism in between physical and chemical adsorption because the hydrogen bonds formed by the overlap of F (p) orbital and H (s) orbital are weak intermolecular interactions while the physical adsorption are mainly ascribed to the electrostatic interactions. This massive calculation provides a new insight into the pollutant adsorption behaviour, and in particular, may help to evaluate the environmental influence of pollutants.

  19. Proparacaine complexation with beta-cyclodextrin and p-sulfonic acid calix[6]arene, as evaluated by varied (1)H-NMR approaches.

    PubMed

    Arantes, Lucas Micquéias; Scarelli, Camilla; Marsaioli, Anita Jocelyne; de Paula, Eneida; Fernandes, Sergio Antonio

    2009-09-01

    This study focused on the use of NMR techniques as a tool for the investigation of complex formation between proparacaine and cyclodextrins (CDs) or p-sulfonic acid calix[6]arene. The pH dependence of the complexation of proparacaine with beta-CD and p-sulfonic acid calix[6]arene was studied and binding constants were determined by (1)H NMR spectroscopy [diffusion-ordered spectroscopy (DOSY)] for the charged and uncharged forms of the local anesthetic in beta-CD and p-sulfonic acid calix[6]arene. The stoichiometries of the complexes was determined and rotating frame Overhauser enhancement spectroscopy (ROESY) 1D experiments revealed details of the molecular insertion of proparacaine into the beta-CD and p-sulfonic acid calix[6]arene cavities. The results unambiguously demonstrate that pH is an important factor for the development of supramolecular architectures based on beta-CD and p-sulfonic acid calix[6]arene as the host molecules. Such host-guest complexes were investigated in view of their potential use as new therapeutic formulations, designed to increase the bioavailability and/or to decrease the systemic toxicity of proparacaine in anesthesia procedures.

  20. Fate of linear alkylbenzene sulfonate (LAS) in activated sludge plants.

    PubMed

    Temmink, H; Klapwijk, Bram

    2004-02-01

    Monitoring data were collected in a pilot-scale municipal activated sludge plant to assess the fate of the C12-homologue of linear alkyl benzene sulfonate (LAS-C12). The pilot-plant was operated at influent LAS-C12 concentrations between 2 and 12 mg l(-1) and at sludge retention times of 10 and 27 days. Effluent and waste sludge concentrations varied between 5 and 10 microg l(-1) and between 37 and 69 microg g(-1) VSS, respectively. In the sludge samples only 2-8% was present as dissolved LAS-C12, whereas the remaining 92-98% was found to be adsorbed to the sludge. In spite of this high degree of sorption, more than 99% of the LAS-C12 load was removed by biodegradation, showing that not only the soluble fraction but also the adsorbed fraction of LAS-C12 is readily available for biodegradation. Sorption and biodegradation of LAS-C12 were also investigated separately. Sorption was an extremely fast and reversible process and could be described by a linear isotherm with a partition coefficient of 3.2 l g(-1) volatile suspended solids. From the results of biodegradation kinetic tests it was concluded that primary biodegradation of LAS-C12 cannot be described by a (growth) Monod model, but a secondary utilisation model should be used instead. The apparent affinity of the sludge to biodegrade LAS-C12 increased when the sludge was loaded with higher influent concentrations of LAS-C12.

  1. Isotopic Measurements of Organic Sulfonates From The Murchison Meteorite

    NASA Technical Reports Server (NTRS)

    Cooper, G. W.; Chang, S.; DeVincenzi, Donald L. (Technical Monitor)

    1995-01-01

    Organic sulfonates and phosphonates have been extracted from the Murchison meteorite for stable isotope measurements. Preliminary stable isotope measurements of individual alkyl sulfonates, R-SO3H (R=C(sub n)H(sub 2n+l)), are shown. These compounds were found in aqueous extracts of Murchison. Both groups show trends similar to other homologous series of organic compounds indigenous to Murchison. Molecular abundances decrease with increasing carbon number, and all possible isomers at each carbon number (through C-4) are present. Carbon isotope measurements of the sulfonates show a decrease in the C-13/C-12 ratio with increasing carbon number. The overall objectives of this project are to obtain dime element carbon, hydrogen, and sulfur - intramolecular isotopic analyses of individual sulfonates, and isotopic measurement of carbon and hydrogen of the phosphonates as a group. The Murchison meteorite is the best characterized carbonaceous chondrite with respect to organic chemistry. The finding of organic sulfonates and phosphonates in Murchison is of interest because they are the first well-characterized series of sulfur and phosphorus containing organic compounds found in meteorites. Also, meteorites, comets, and interplanetary dust particles may have been involved in chemical evolution on the early Earth. Because of the critical role of organic phosphorus and sulfur in all living systems, it is particularly interesting to see examples of abiotic syntheses of these classes of compounds. The study of the isotopic composition of the sulfonates and phosphonates can yield insight into their possible interstellar origin as well as their mechanisms of synthesis in the early solar system. Previous isotopic analyses of other classes of organic compounds indigenous to meteorites, e.g., amino acids, carboxylic acids, and hydrocarbons indicate the possibility that interstellar molecules were incorporated into meteorite parent bodies. In these compounds the ratios of heavy to

  2. Discovery of novel sulfonated small molecules that inhibit vascular tube formation

    PubMed Central

    Raman, Karthik; Karuturi, Rajesh; Swarup, Vimal P.; Desai, Umesh R.; Kuberan, Balagurunathan

    2012-01-01

    Tumor-associated angiogenesis is a complex process that involves the interplay among several molecular players such as cell-surface heparan sulfate proteoglycans, vascular endothelial growth factors and their cognate receptors. PI-88, a highly sulfonated oligosaccharide, has been shown to have potent anti-angiogenic activity and is currently in clinical trials. However, one of the major drawbacks of large oligosaccharides such as PI-88 is that their synthesis often requires numerous complex synthetic steps. In this study, several novel polysulfonated small molecule carbohydrate mimetics, which can easily be synthesized in fewer steps, are identified as promising inhibitors of angiogenesis in an in vitro tube formation assay. PMID:22627041

  3. Synthesis of Sulfones and Sulfonamides via Sulfinate Anions: Revisiting the Utility of Thiosulfonates.

    PubMed

    Shyam, Pranab K; Jang, Hye-Young

    2017-02-03

    Simple and high-yielding strategies for the production of a variety of sulfones and sulfonamides, using thiosulfonates synthesized by copper-catalyzed aerobic dimerization, are reported. Although thiosulfonates are an old class of compound, practical methods for their synthesis and utilization have not been rigorously developed. In this study, we revisit the reactions of easily accessible thiosulfonates to form sulfinate anions. Because of the similar reactivity of thiosulfonates and metal sulfinates derived from toxic SO2, thiosulfinates are proposed to be stable, nontoxic alternatives to metal sulfinate salts.

  4. Improved oral absorption of cilostazol via sulfonate salt formation with mesylate and besylate

    PubMed Central

    Seo, Jae Hong; Park, Jung Bae; Choi, Woong-Kee; Park, Sunhwa; Sung, Yun Jin; Oh, Euichaul; Bae, Soo Kyung

    2015-01-01

    Objective Cilostazol is a Biopharmaceutical Classification System class II drug with low solubility and high permeability, so its oral absorption is variable and incomplete. The aim of this study was to prepare two sulfonate salts of cilostazol to increase the dissolution and hence the oral bioavailability of cilostazol. Methods Cilostazol mesylate and cilostazol besylate were synthesized from cilostazol by acid addition reaction with methane sulfonic acid and benzene sulfonic acid, respectively. The salt preparations were characterized by nuclear magnetic resonance spectroscopy. The water contents, hygroscopicity, stress stability, and photostability of the two cilostazol salts were also determined. The dissolution profiles in various pH conditions and pharmacokinetic studies in rats were compared with those of cilostazol-free base. Results The two cilostazol salts exhibited good physicochemical properties, such as nonhygroscopicity, stress stability, and photostability, which make it suitable for the preparation of pharmaceutical formulations. Both cilostazol mesylate and cilostazol besylate showed significantly improved dissolution rate and extent of drug release in the pH range 1.2–6.8 compared to the cilostazol-free base. In addition, after oral administration to rats, cilostazol mesylate and cilostazol besylate showed increases in Cmax and AUCt of approximately 3.65- and 2.87-fold and 3.88- and 2.94-fold, respectively, compared to cilostazol-free base. Conclusion This study showed that two novel salts of cilostazol, such as cilostazol mesylate and cilostazol besylate, could be used to enhance its oral absorption. The findings warrant further preclinical and clinical studies on cilostazol mesylate and cilostazol besylate at doses lower than the usually recommended dosage, so that it can be established as an alternative to the marketed cilostazol tablet. PMID:26251575

  5. Steady-state inhibition model for the biodegradation of sulfonated amines in a packed bed reactor.

    PubMed

    Juárez-Ramírez, Cleotilde; Galíndez-Mayer, Juvencio; Ruiz-Ordaz, Nora; Ramos-Monroy, Oswaldo; Santoyo-Tepole, Fortunata; Poggi-Varaldo, Héctor

    2015-05-25

    Aromatic amines are important industrial products having in their molecular structure one or more aromatic rings. These are used as precursors for the synthesis of dyes, adhesives, pesticides, rubber, fertilizers and surfactants. The aromatic amines are common constituents of industrial effluents, generated mostly by the degradation of azo dyes. Several of them are a threat to human health because they can by toxic, allergenic, mutagenic or carcinogenic. The most common are benzenesulfonic amines, such as 4-ABS (4-aminobenzene sulfonic acid) and naphthalene sulfonic amines, such as 4-ANS (4-amino naphthalene sulfonic acid). Sometimes, the mixtures of toxic compounds are more toxic or inhibitory than the individual compounds, even for microorganisms capable of degrading them. Therefore, the aim of this study was to evaluate the degradation of the mixture 4-ANS plus 4-ABS by a bacterial community immobilized in fragments of volcanic stone, using a packed bed continuous reactor. In this reactor, the amines loading rates were varied from 5.5 up to 69 mg L(-1) h(-1). The removal of the amines was determined by high-performance liquid chromatography and chemical oxygen demand. With this information, we have studied the substrate inhibition of the removal rate of the aromatic amines during the degradation of the mixture of sulfonated aromatic amines by the immobilized microorganisms. Experimental results were fitted to parabolic, hyperbolic and linear inhibition models. The model that best characterizes the inhibition of the specific degradation rate in the biofilm reactor was a parabolic model with values of RXM=58.15±7.95 mg (10(9) cells h)(-1), Ks=0.73±0.31 mg L(-1), Sm=89.14±5.43 mg L(-1) and the exponent m=5. From the microbial community obtained, six cultivable bacterial strains were isolated and identified by sequencing their 16S rDNA genes. The strains belong to the genera Variovorax, Pseudomonas, Bacillus, Arthrobacter, Nocardioides and Microbacterium. This

  6. Degradation of Alkyl Benzene Sulfonate by Pseudomonas Species1

    PubMed Central

    Horvath, R. S.; Koft, B. W.

    1972-01-01

    Pseudomonas sp. HK-1 showed a direct relation between the concentration of alkyl benzene sulfonate (ABS) supplied and cell yields. Since growth on ABS alone did not occur, it was necessary to correlate the total energy obtained by the cells to the ABS concentration when glucose was supplied in a limiting concentration. Several types of metabolic attack in addition to the sulfonate removal were noted: (i) side-chain utilization as indicated by the production of tertiarybutyl alcohol and isopropanol and (ii) ring metabolism as indicated by the presence of phenol, catechol, mandelic acid, benzyl alcohol, and benzoic acid in spent growth media. Utilization of ABS was greatly enhanced by the presence of phenol. This enhancement suggests co-metabolism and that limited concentrations of phenolic products derived from ABS must be accumulated to get active metabolism of the ABS molecule. PMID:5017680

  7. Electron microscope studies of overbased sulfonates with various cations

    SciTech Connect

    Mishunina, I.I.; Fialkovskii, R.V.; Mysak, N.P.; Romanyutina, L.V.

    1983-03-01

    This article examines overbased sulfonates containing anionic detergents with magnesium, calcium, strontium, or barium cations and the corresponding metal carbonates. Uses direct transmission microscopy, in which 2 planar coordinates of the object can be evaluated, to determine the dimensions of the inorganic part of the colloidal particles of the additives and to establish their geometric shape through projection on the plane (on the basis of which conclusions can be drawn as to the crystalline or amorphous structure of the solid phase). Finds that the different cations lead to changes in the colloidal structure of the additives. This is reflected in the dimensions of the micelle cores and of the adsorbed shells (with comparable total alkalinity of the additives and similar contents of neutral detergents in the hydroxide, and sulfonate per unit volume of additive, ultimately being reflected in the service properties of additives that are identical or very similar in characteristics but different in the particular metal cation.

  8. Permselectivity and conductivity of membranes based on sulfonated naphthalenic copolyimides.

    PubMed

    Guo, Xiaoxia; Zhai, Fengxia; Fang, Jianhua; Laguna, Maria Fe; López-Gonzalez, Mar; Riande, Evaristo

    2007-12-13

    A series of sulfonated diamines were synthesized which were further used to obtain relevant sulfonated naphthalenic copolyimides. Tough and ductile membranes were cast from solutions of the copolyimides in dimethylsulfoxide, which exhibit high ion-exchange capacity and high water uptake. The protonic conductivity of the membranes equilibrated with water lies in the range 1.0-8.6 S/m, at 25 degrees C, being of the same order of magnitude as that reported for perfluorinated acidic membranes. The values of the transport number of protons and sodium ions are close to the unit for very dilute electrolyte solutions, but they lie in the range 0.80-0.90 for moderate concentrations. The membranes exhibit rather high electroosmotic permeability. The similarity of the diffusion coefficients of protons and water in the membranes suggests that the Grottus mechanism governs the protonic conductive process in the acidic membranes equilibrated with water.

  9. Synthesis of 3-O-sulfonated heparan sulfate octasaccharides that inhibit the herpes simplex virus type 1 host-cell interaction

    NASA Astrophysics Data System (ADS)

    Hu, Yu-Peng; Lin, Shu-Yi; Huang, Cheng-Yen; Zulueta, Medel Manuel L.; Liu, Jing-Yuan; Chang, Wen; Hung, Shang-Cheng

    2011-07-01

    Cell surface carbohydrates play significant roles in a number of biologically important processes. Heparan sulfate, for instance, is a ubiquitously distributed polysulfated polysaccharide that is involved, among other things, in the initial step of herpes simplex virus type 1 (HSV-1) infection. The virus interacts with cell-surface heparan sulfate to facilitate host-cell attachment and entry. 3-O-Sulfonated heparan sulfate has been found to function as an HSV-1 entry receptor. Achieving a complete understanding of these interactions requires the chemical synthesis of such oligosaccharides, but this remains challenging. Here, we present a convenient approach for the synthesis of two irregular 3-O-sulfonated heparan sulfate octasaccharides, making use of a key disaccharide intermediate to acquire different building blocks for the oligosaccharide chain assembly. Despite substantial structural differences, the prepared 3-O-sulfonated sugars blocked viral infection in a dosage-dependent manner with remarkable similarity to one another.

  10. New Fluorinated and Sulfonated Block Copolymers Final Report

    DTIC Science & Technology

    2009-04-23

    serves as a plasticizer even in the hydrophobic FI domain. Similar glass transition reduction effects observed in other ionomer systems have been...Sulfonated Ionomer : Thermal Annealing and Solvent Effects.” American Physical Society National Meeting. Los Angeles, CA. March 21, 2005. 4. Akinbode...optimizing morphology and ultimately properties, membranes have been cast from relatively inexpensive block-copolymer ionomers of fluorinated poly

  11. The Snail-Induced Sulfonation Pathway in Breast Cancer Metastasis

    DTIC Science & Technology

    2013-07-01

    1 AD_________________ Award Number: W81XWH-11-1-0494 TITLE: The Snail -Induced Sulfonation...REPORT TYPE Annual 3. DATES COVERED 1 July 2012 - 30 June 2013 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER W81XWH-11-1-0494 The Snail -induced...support: 1. Further characterization of Tetracycline inducible WT Snail and mutant Snail vectors and cell lines. 2. Demonstration that the PAPSS2

  12. Formulation of soluble oils with synthetic and petroleum sulfonates

    SciTech Connect

    Eckard, A.; Riff, I.; Weaver, J.

    1997-06-01

    Metalworking fluids for metal removal are formulated to provide cooling, lubrication, and rust protection when cutting and machining metals. There are basically four types of cutting fluids: straight oils, synthetics, semisynthetic fluids and soluble oils. The last type is the most widely used for metal removal operations such as cutting, drilling and grinding. Soluble oils used for metalworking operations are normally the oil-in-water type, with oil as the internal phase and water as the external phase. The soluble oils can have rather complex compositions, usually containing two or more emulsifiers and coupling agents, as well as additives to provide rust inhibition, lubricity, detergency, resistance to bacterial attack and foam control. The dominant emulsifier in a soluble oil is usually sodium sulfonate which also has the secondary benefit of being a rust inhibitor. Soluble oil emulsions based on petroleum or synthetic sulfonates have been found to improve lubrication and cleaning of metal parts and equipment. As has been done previously, a series of emulsification studies were conducted using petroleum and synthetic sulfonates. Emulsifier level, coemulsifiers and minor formulation adjustments were made to optimize each system. This study was made using naphthenic oil basestock. Formulations were evaluated using criteria including concentrate stability, hard and soft water emulsion stability, emulsibility, foaming tendency and response to defoamers, antirust properties and cost effectiveness of individual formulations. The results of these evaluations are presented in the present paper.

  13. Preparation and Characterization of Sulfonic Acid Functionalized Silica and Its Application for the Esterification of Ethanol and Maleic Acid

    NASA Astrophysics Data System (ADS)

    Sirsam, Rajkumar; Usmani, Ghayas

    2016-04-01

    The surface of commercially available silica gel, 60-200 mesh size, was modified with sulfonic acid through surface activation, grafting of 3-Mercaptopropyltrimethoxysilane, oxidation and acidification of 3-Mercaptopropylsilica. Sulfonic Acid Functionalization of Silica (SAFS) was confirmed by Fourier Transform Infra-red (FTIR) spectroscopy and thermal gravimetric analysis. Acid-base titration was used to estimate the cation exchange capacity of the SAFS. Catalytic activity of SAFS was judged for the esterification of ethanol with maleic acid. An effect of different process parameters viz. molar ratio, catalyst loading, speed of agitation and temperature were studied and optimized by Box Behnken Design (BBD) of Response Surface Methodology (RSM). Quadratic model developed by BBD-RSM reasonably satisfied an experimental and predicted values with correlation coefficient value R2 = 0.9504.

  14. Cross-linked sulfonated poly(ether ether ketone) by using diamino-organosilicon for proton exchange fuel cells.

    PubMed

    Kayser, Marie J; Reinholdt, Marc X; Kaliaguine, Serge

    2011-03-31

    Fuel cells are at the battlefront to find alternate sources of energy to the highly polluting, economically and environmentally constraining fossil fuels. This work uses an organosilicon molecule presenting two amine functions, bis(3-aminopropyl)-tetramethyldisiloxane (APTMDS) with the aim of preparing cross-linked sulfonated poly(ether ether ketone) (SPEEK) based membranes. The hybrid membranes obtained at varying APTMDS loadings are characterized for their acid, proton conductivity, water uptake, and swelling properties. APTMDS may be considered as an extreme case of silica nanoparticle and is therefore most advantageously distributed within the polymeric matrix. The two amine groups can interact, via electrostatic interactions, with the sulfonic acid groups of SPEEK, resulting in a double anchoring of the molecule. The addition of a small amount of APTMDS is enhancing the mechanical and hydrolytic properties of the membranes and allows some unfolding of the polymer chains, rendering some acid sites accessible to water molecules and thus available for proton transport.

  15. Detection of a cyclic perfluorinated acid, perfluoroethylcyclohexane sulfonate, in the Great Lakes of North America.

    PubMed

    De Silva, Amila O; Spencer, Christine; Scott, Brian F; Backus, Sean; Muir, Derek C G

    2011-10-01

    Perfluoroethylcyclohexanesulfonate (PFECHS) is a cyclic perfluorinated acid (PFA) mainly used as an erosion inhibitor in aircraft hydraulic fluids. It is expected to be as recalcitrant to environmental degradation as aliphatic PFAs including perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS). For the first time, PFECHS is reported in top predator fish (An impurity in the commercial PFECHS formulation, perfluoromethylcyclohexane sulfonate (PFMeCHS), was also detected in the dissolved phase but not above detection limits in fish tissue. Bioaccumulation factors (BAFs) were estimated by taking the ratio of fish to water concentrations. The mean log BAF values corresponded to 2.8 for PFECHS, 2.1 for PFOA, and 4.5 for PFOS. It is not certain whether the fish-water BAF for PFECHS is an overestimate due to the influence of precursor biotransformation. Further studies are recommended to understand the extent of PFECHS contamination.

  16. Sulfonated polyaniline-based organic electrodes for controlled electrical stimulation of human osteosarcoma cells.

    PubMed

    Min, Yong; Yang, Yanyin; Poojari, Yadagiri; Liu, Yidong; Wu, Jen-Chieh; Hansford, Derek J; Epstein, Arthur J

    2013-06-10

    Electrically conducting polymers (CPs) were found to stimulate various cell types such as neurons, osteoblasts, and fibroblasts in both in vitro and in vivo studies. However, to our knowledge, no studies have been reported on the utility of CPs in stimulation of cancer or tumor cells in the literature. Here we report a facile fabrication method of self-doped sulfonated polyaniline (SPAN)-based interdigitated electrodes (IDEs) for controlled electrical stimulation of human osteosarcoma (HOS) cells. Increased degree of sulfonation was found to increase the SPAN conductivity, which in turn improved the cell attachment and cell growth without electrical stimulation. However, an enhanced cell growth was observed under controlled electrical (AC) stimulation at low applied voltage and frequency (≤800 mV and ≤1 kHz). The cell growth reached a maximum threshold at an applied voltage or frequency and beyond which pronounced cell death was observed. We believe that these organic electrodes may find utility in electrical stimulation of cancer or tumor cells for therapy and research and may also provide an alternative to the conventional metal-based electrodes.

  17. Fabrication and characterization of amine terminated poly(arylene ether sulfone) modified epoxy-carbon fiber composites

    NASA Technical Reports Server (NTRS)

    Cecere, James A.; Senger, James S.; Mcgrath, James E.; Steiner, Paul A.; Wong, Raymond S.

    1987-01-01

    Multifunctional epoxy resin networks were chemically modified with thermoplastic amine terminated poly(arylene ether sulfones) of controlled molecular weights. This system was then examined as both neat resin and as a matrix resin for carbon fiber composites. The neat resin displayed a significant increase in both fracture toughness and energy release rate values. This was attributed to the altered morphology, which could be varied from particles of polysulfone in an epoxy matrix to that of a quasi-continuous polysulfone phase.

  18. Inorganic base-catalyzed formation of antivirally active N-substituted benzamides from α-amido sulfones and N-nucleophile

    PubMed Central

    2011-01-01

    Background Heteronucleophiles as well as carbanionic reagents can be used to react with α-amido sulfones, thus giving the opportunity to prepare a large array of amino derivatives. Since, novel 1,3,4-oxadiazole-2-thiol derivatives can serve as potent nucleophiles, we employed 5-subsititued phenyl-1,3,4-oxadiazole-2-thiols as the nucleophilic source of nitrogen in the reaction with α-amido sulfones. Results A series of N-substituted benzamides bearing 1,3,4-oxadiazol unit were prepared for the first time by the reaction of in situ generated protected imine from α-amido sulfones with 5-subsititued phenyl-1,3,4-oxadiazole-2-thiols as the source of nitrogen nucleophile. Some of the synthesized products displayed favourable antiviral activity against cucumber mosaic virus (CMV) in preliminary antiviral activity tests. The title compounds 5c, 5o and 5r revealed curative activity of 42.2%, 48.7% and 40.5%, respectively against CMV (inhibitory rate) compared to the commercial standard Ningnanmycin (53.4%) at 500 μg/mL. Conclusion A practical synthetic route to N-benzoyl-α-amido sulfones by the reaction of 5-subsititued phenyl-1,3,4-oxadiazole-2-thiols as the source of nitrogen nucleophiles with in situ generated protected imine from N-benzoyl-α-amido sulfones is presented. The reaction catalyzed by an inorganic base has considerable significance to exploit the potential of α-amido sulfones in organic synthesis. PMID:21545729

  19. First synthesis and antiprotozoal activities of divinyl sulfone-modified carbohydrates.

    PubMed

    Pal, Tarun Kumar; Dey, Tuli; Chakrabarty, Arindam; Dey, Debanjana; Ghosh, Sudip K; Pathak, Tanmaya

    2010-06-15

    Divinyl sulfone-modified carbohydrates have been synthesized for the first time by reacting easily available carbohydrate epoxides with thioethanol in a regiospecific fashion. One of the modified divinyl sulfones initiated significant cell death in Entamoeba species and the influence of the anomeric configurations on the biological activities of these sugar-derived divinyl sulfones has been highlighted. The most active compound in this series was found to be devoid of any toxicity.

  20. Ileum and colon perforation following peritoneal dialysis-related peritonitis and high-dose calcium polystyrene sulfonate.

    PubMed

    Kao, Chih-Chin; Tsai, Yi-Chiun; Chiang, Wen-Chih; Mao, Tsui-Lien; Kao, Tze-Wah

    2015-10-01

    A rare but severe complication, intestinal necrosis, has been reported after sodium polystyrene sulfonate (SPS; Kayexalate) and sorbitol intake. Some case reports described bowel perforation following calcium polystyrene sulfonate (CPS; Kalimate) administration. We report a case of ileum and colon perforation following peritoneal dialysis-related peritonitis and high-dose Kalimate in a 59-year-old female patient. The patient had a history of hypertension, diabetes mellitus, and end-stage renal disease (ESRD). During hospitalization for peritoneal dialysis-related peritonitis, she developed hyperkalemia, and Kalimate was administered orally. However, severe abdominal distension and pain occurred just one day after Kalimate intake. An urgent surgery disclosed several perforations in the ileum and sigmoid colon. Pathology of the resected gut showed transmural necrosis and perforation with basophilic angulated crystals. The patient finally expired during hospitalization due to refractory septic shock.

  1. Syntheses of biodiesel precursors: sulfonic acid catalysts for condensation of biomass-derived platform molecules.

    PubMed

    Balakrishnan, Madhesan; Sacia, Eric R; Bell, Alexis T

    2014-04-01

    Synthesis of transportation fuel from lignocellulosic biomass is an attractive solution to the green alternative-energy problem. The production of biodiesel, in particular, involves the process of upgrading biomass-derived small molecules to diesel precursors containing a specific carbon range (C11 -C23). Herein, a carbon-upgrading process utilizing an acid-catalyzed condensation of furanic platform molecules from biomass is described. Various types of sulfonic acid catalysts have been evaluated for this process, including biphasic and solid supported catalysts. A silica-bound alkyl sulfonic acid catalyst has been developed for promoting carbon-carbon bond formation of biomass-derived carbonyl compounds with 2-methylfuran. This hydrophobic solid acid catalyst exhibits activity and selectivity that are comparable to those of a soluble acid catalyst. The catalyst can be readily recovered and recycled, possesses appreciable hydrolytic stability in the presence of water, and retains its acidity over multiple reaction cycles. Application of this catalyst to biomass-derived platform molecules led to the synthesis of a variety of furanic compounds, which are potential biodiesel precursors.

  2. Calcium carbonate phase transformations during the carbonation reaction of calcium heavy alkylbenzene sulfonate overbased nanodetergents preparation.

    PubMed

    Chen, Zhaocong; Xiao, Shan; Chen, Feng; Chen, Dongzhong; Fang, Jianglin; Zhao, Min

    2011-07-01

    The preparation and application of overbased nanodetergents with excess alkaline calcium carbonate is a good example of nanotechnology in practice. The phase transformation of calcium carbonate is of extensive concern since CaCO(3) serves both as an important industrial filling material and as the most abundant biomineral in nature. Industrially valuable overbased nanodetergents have been prepared based on calcium salts of heavy alkylbenzene sulfonate by a one-step process under ambient pressure, the carbonation reaction has been monitored by the instantaneous temperature changes and total base number (TBN). A number of analytical techniques such as TGA, DLS, SLS, TEM, FTIR, and XRD have been utilized to explore the carbonation reaction process and phase transformation mechanism of calcium carbonate. An enhanced understanding on the phase transformation of calcium carbonate involved in calcium sulfonate nanodetergents has been achieved and it has been unambiguously demonstrated that amorphous calcium carbonate (ACC) transforms into the vaterite polymorph rather than calcite, which would be of crucial importance for the preparation and quality control of lubricant additives and greases. Our results also show that a certain amount of residual Ca(OH)(2) prevents the phase transformation from ACC to crystalline polymorphs. Moreover, a vaterite nanodetergent has been prepared for the first time with low viscosity, high base number, and uniform particle size, nevertheless a notable improvement on its thermal stability is required for potential applications.

  3. Preparation of sulfonic acid-containing rubbers from natural rubber vulcanizates

    NASA Astrophysics Data System (ADS)

    Poonsawat, Worapong; Poompradub, Sirilux; Ngamcharussrivichai, Chawalit

    2014-06-01

    In this work, a series of sulfonic acid-containing rubbers were prepared by aqueous phase oxidation of natural rubber vulcanizates in the presence of hydrogen peroxide (H2O2) and formic acid (HCOOH). The starting vulcanizates were neatly prepared via an efficient vulcanization (EV) system by varying mass ratio of N-cyclohexyl-2-benzothiazole sulfonamide (CBS), as an accelerator, to sulfur. The oxidation conditions were controlled at the molar ratio of H2O2: HCOOH = 1:1, the concentration of H2O2 = 15 wt.%, the temperature = 50 °C, and the reaction time = 3 h. The rubber materials before and after the oxidation were characterized for their physicochemical properties by using Fourier transform infrared spectroscopy, bomb calorimetry, acid-base titration and swelling measurements. The results indicated the presence of sulfonic acid group in the oxidized rubbers, generated by the oxidative cleaves of sulfide crosslinks in the rubber vulcanizates. The oxidation decreased the sulfur content of the rubber in which the level of sulfur loss was determined by the CBS/sulfur ratio. Moreover, the acidity of the oxidized products was correlated with the amount of sulfur remaining.

  4. Penicillanic acid sulfone: nature of irreversible inactivation of RTEM beta-lactamase from Escherichia coli.

    PubMed

    Brenner, D G; Knowles, J R

    1984-11-20

    When penicillanic acid sulfone in large molar excess is incubated with the RTEM beta-lactamase, the enzyme becomes inactivated irreversibly. From studies of the consequential spectroscopic changes, from the use of specifically tritiated penicillanic acid sulfone, and from comparison by isoelectric focusing of the enzyme after inactivation by the sulfone and by clavulanic acid, the inactivated enzyme appears to be cross-linked by a beta-aminoacrylate fragment deriving from C-5, C-6, and C-7 of the original beta-lactam. Model studies on the behavior of alcoholic solutions of penicillanic acid sulfone in the presence of amines are entirely consistent with this interpretation.

  5. Sulfonates: A novel class of organic sulfur compounds in marine sediments

    NASA Astrophysics Data System (ADS)

    Vairavamurthy, Appathurai; Zhou, Weiqing; Eglinton, Timothy; Manowitz, Bernard

    1994-11-01

    X-ray absorption near-edge structure spectroscopy (XANES) used to measure sulfur speciation in a variety of organic-rich marine sediments has established sulfonates as a novel and major component of sedimentary organic sulfur. The origins of sulfonates in sediments are not clear, although both biological and geochemical mechanisms are possible. The accumulation of oxidized sulfonate sulfur in reducing marine sediments was not known previously; hence, a new perspective in sulfur geochemistry is established. The biogeochemical implications of the presence of sulfonates in marine sediments are discussed.

  6. Quinone-mediated decolorization of sulfonated azo dyes by cells and cell extracts from Sphingomonas xenophaga.

    PubMed

    Jiao, Ling; Lu, Hong; Zhou, Jiti; Wang, Jing

    2009-01-01

    The effects of various quinone compounds on the decolorization rates of sulfonated azo dyes by Sphingomonas xenophaga QYY were investigated. The results showed that anthraquinone-2-sulfonate (AQS) was the most effective redox mediator and AQS reduction was the rate-limited step of AQS-mediated decolorization of sulfonated azo dyes. Based on AQS biological toxicity tests, it was assumed that AQS might enter the cells and kill them. In the cytoplasmic extracts from strain QYY, AQS more effectively increased decolorization rates of sulfonated azo dyes than other quinone compounds. In addition, we found a NADH/FMN-dependent AQS reductase using nondenaturing polyacrylamide gel electrophoresis (Native-PAGE).

  7. Determination of methiocarb and its degradation products, methiocarb sulfoxide and methiocarb sulfone, in bananas using QuEChERS extraction.

    PubMed

    Plácido, Alexandra; Paíga, Paula; Lopes, David H; Correia, Manuela; Delerue-Matos, Cristina

    2013-01-16

    The present work describes the development of an analytical method for the determination of methiocarb and its degradation products (methiocarb sulfoxide and methiocarb sulfone) in banana samples, using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure followed by liquid chromatography coupled to photodiode array detector (LC-PAD). Calibration curves were linear in the range of 0.5-10 mg L⁻¹ for all compounds studied. The average recoveries, measured at 0.1 mg kg⁻¹ wet weight, were 92.0 (RSD = 1.8%, n = 3), 84.0 (RSD = 3.9%, n = 3), and 95.2% (RSD = 1.9%, n = 3) for methiocarb sulfoxide, methiocarb sulfone, and methiocarb, respectively. Banana samples treated with methiocarb were collected from an experimental field. The developed method was applied to the analysis of 24 samples (peel and pulp) and to 5 banana pulp samples. Generally, the highest levels were found for methiocarb sulfoxide and methiocarb. Methiocarb sulfone levels were below the limit of quantification, except in one sample (not detected).

  8. Effects of bleach activator, sodium alkyl acyloxybenzene sulfonate, on house dust mites (Dermatophagoides farinae).

    PubMed

    Tobe, Seiichi; Kamezaki, Hiroki; Watanabe, Toshiyuki; Takaoka, Hiromitsu; Sakaguchi, Masahiro

    2010-01-01

    House dust mites (Dermatophagoides farinae) in bedding and clothes are a major allergen. However, house dust mites cannot be killed by general washing conditions under 50 degrees C. Therefore, low-temperature washing conditions must be improved to eliminate house dust mites. Sodium alkyl acyloxybenzene sulfonate (OBS) is a bleach activator that is used to intensify the bleaching effects of some laundry products. The purpose of this study was to evaluate the effect of OBS on the elimination of house dust mites in low-temperature washing conditions. D. farinae was soaked in solutions containing different types of OBS for various durations and at various temperatures. The miticidal effects of the various washing conditions were also evaluated for D. farinae. Then sodium lauroyloxybenzene sulfonate (OBS-12) produced the highest D. farinae mortality rate among the OBS solutions that were examined and had a stronger miticidal effect than available chlorine under general washing conditions. OBS exhibited miticidal effects under general washing conditions at low temperatures. Since OBS is already used as an additive in some laundry products to increase the bleaching activity, OBS can be easily used to kill house dust mites under general washing conditions.

  9. Synthesis, characterization, antibacterial activity and quantum chemical studies of N'-Acetyl propane sulfonic acid hydrazide

    NASA Astrophysics Data System (ADS)

    Alyar, Saliha; Alyar, Hamit; Ozdemir, Ummuhan Ozmen; Sahin, Omer; Kaya, Kerem; Ozbek, Neslihan; Gunduzalp, Ayla Balaban

    2015-08-01

    A new N'-Acetyl propane sulfonic acid hydrazide, C3H7sbnd SO2sbnd NHsbnd NHsbnd COCH3 (Apsh, an sulfon amide compound) has been synthesized for the first time. The structure of Apsh was investigated using elemental analysis, spectral (IR, 1H/13C NMR) measurements. In addition, molecular structure of the Apsh was determined by single crystal X-ray diffraction technique and found that the compound crystallizes in monoclinic, space group P 21/c. 1H and 13C shielding tensors for crystal structure were calculated with GIAO/DFT/B3LYP/6-311++G(d,p) methods in CDCl3. The structure of Apsh is optimized using Density Functional Theory (DFT) method. The vibrational band assignments were performed at B3LYP/6-311++G(d,p) theory level combined with scaled quantum mechanics force field (SQMFF) methodology. The theoretical IR frequencies are found to be in good agreement with the experimental IR frequencies. Nonlinear optical (NLO) behaviour of Apsh is also examined by the theoretically predicted values of dipole moment (μ), polarizability (α0) and first hyperpolarizability (βtot). The antibacterial activities of synthesized compound were studied against Gram positive bacteria: Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 23212, Staphylococcus epidermidis ATCC 34384, Gram negative bacteria: Eschericha coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 70063 by using microdilution method (as MICs) and disc diffusion method.

  10. Ionic liquids composed of phosphonium cations and organophosphate, carboxylate, and sulfonate as lubricant antiwear additives

    DOE PAGES

    Zhou, Yan; Dyck, Jeffrey; Graham, Todd; ...

    2014-10-20

    Oil-soluble phosphonium-based ionic liquids (ILs) have recently been reported as potential ashless lubricant additives. This study is to expand the IL chemistry envelope and to achieve fundamental correlations between the ion structures and ILs’ physiochemical and tribological properties. Here we present eight ILs containing two different phosphonium cations and seven different anions from three groups: organophosphate, carboxylate, and sulfonate. The oil solubility of ILs seems largely governed by the IL molecule size and structure complexity. When used as oil additives, the ranking of effectiveness in wear protection for the anions are: organophosphate > carboxylate > sulfonate. All selected ILs outperformedmore » a commercial ashless anti-wear additive. Surface characterization from the top and the cross-section revealed the nanostructures and compositions of the tribo-films formed by the ILs. Some fundamental insights were achieved: branched and long alkyls improve the IL’s oil solubility, anions of a phosphonium-phosphate IL contribute most phosphorus in the tribofilm, and carboxylate anions, though free of P, S, N, or halogen, can promote the formation of an anti-wear tribofilm.« less

  11. Pendant dual sulfonated poly(arylene ether ketone) proton exchange membranes for fuel cell application

    NASA Astrophysics Data System (ADS)

    Nguyen, Minh Dat Thinh; Yang, Sungwoo; Kim, Dukjoon

    2016-10-01

    Poly(arylene ether ketone) (PAEK) possessing carboxylic groups at the pendant position is synthesized, and the substitution degree of pendant carboxylic groups is controlled by adjusting the ratio of 4,4-bis(4-hydroxyphenyl)valeric acid and 2,2-bis(4-hydroxyphenyl)propane. Dual sulfonated 3,3-diphenylpropylamine (SDPA) is grafted onto PAEK as a proton-conducting moiety via the amidation reaction with carboxylic groups. The transparent and flexible membranes with different degrees of sulfonation are fabricated so that we can test and compare their structure and properties with a commercial Nafion® 115 membrane for PEMFC applications. All prepared PAEK-SDPA membranes exhibit good oxidative and hydrolytic stability from Fenton's and high temperature water immersion test. SAXS analysis illustrates an excellent phase separation between the hydrophobic backbone and hydrophilic pendant groups, resulting in big ionic clusters. The proton conductivity was measured at different relative humidity, and its behavior was analyzed by hydration number of the membrane. Among a series of membranes, some samples (including B20V80-SDPA) show not only higher proton conductivity, but also higher integrated cell performance than those of Nafion® 115 at 100% relative humidity, and thus we expect these to be good candidate membranes for proton exchange membrane fuel cells (PEMFCs).

  12. Modification of the cellulosic component of hemp fibers using sulfonic acid derivatives: Surface and thermal characterization.

    PubMed

    George, Michael; Mussone, Paolo G; Bressler, David C

    2015-12-10

    The aim of this study was to characterize the surface, morphological, and thermal properties of hemp fibers treated with two commercially available, inexpensive, and water soluble sulfonic acid derivatives. Specifically, the cellulosic component of the fibers were targeted, because cellulose is not easily removed during chemical treatment. These acids have the potential to selectively transform the surfaces of natural fibers for composite applications. The proposed method proceeds in the absence of conventional organic solvents and high reaction temperatures. Surface chemical composition and signature were measured using gravimetric analysis, X-ray photoelectron spectroscopy (XPS) and Fourier transform infra-red spectroscopy (FTIR). XPS data from the treated hemp fibers were characterized by measuring the reduction in O/C ratio and an increase in abundance of the C-C-O signature. FTIR confirmed the reaction with the emergence of peaks characteristic of disubstituted benzene and amino groups. Grafting of the sulfonic derivatives resulted in lower surface polarity. Thermogravimetric analysis revealed that treated fibers were characterized by lower percent degradation between 200 and 300 °C, and a higher initial degradation temperature.

  13. Virucidal effects of bleach activators, sodium alkyl acyloxybenzene sulfonate and acyloxybenzoic acid, against Feline calicivirus.

    PubMed

    Tobe, Seiichi; Hoshi, Marika; Iizuka, Kinue; Tadenuma, Hirohiko; Takaoka, Hiromitsu; Komoriya, Tomoe; Kohno, Hideki

    2012-01-01

    Noroviruses (NVs) are major causative pathogens of gastroenteritis. The disinfection of contaminated clothing during common household washing is desirable. The virucidal effects of 2 bleach activators, sodium alkyl acyloxybenzene sulfonate (OBS) and alkyl acyloxybenzoic acid (OBC), were studied using Feline calicivirus (FCV) as a surrogate for NVs. FCV was added to solutions containing either OBS or OBC and sodium percarbonate at various temperatures and for varying lengths of time. OBS and OBC, which generate long carbon chain peroxy acids, enhanced the virucidal effect of sodium percarbonate (PC). In particular, sodium lauroyloxybenzene sulfonate (OBS-12) and decanoyloxybenzoic acid (OBC-10) showed superior virucidal effects. Although the virucidal effect of 38-200 mg/L OBS-12 was maintained with 2-5% (v/v) horse serum, there was less of an effect with the same concentration of available chlorine. OBS and OBC have been used as ingredients in some laundry products to increase bleaching activity. It is expected that the use of OBS and OBC is also effective for the inactivation of NVs under common household washing conditions.

  14. Carbon nanotubes-blended poly(phenylene sulfone) membranes for ultrafiltration applications

    NASA Astrophysics Data System (ADS)

    Lawrence Arockiasamy, D.; Alam, Javed; Alhoshan, Mansour

    2013-03-01

    Multi-walled carbon nanotubes (MWCNT) were carboxylated by a chemical method. Poly(phenylene sulfone) (PPSU), MWCNT and functionalized (carboxylated) MWCNT/poly(phenylene sulfone) (PPSU) blend membranes were synthesized via the phase-inversion method. The resultant membranes were then characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle. The FMWCNT blend membranes appeared to be more hydrophilic, with higher pure water flux than did the pure PPSU and MWCNT/PPSU blend membranes. It was also found that the presence of multi-walled carbon nanotubes (MWCNTs) in the blend membranes was an important factor affecting the morphology and permeation properties of the membranes. The model proteins such as trypsin (20 kDa), pepsin (35 kDa), egg albumin (45 kDa) and bovine serum albumin (69 kDa) rejection experiments were carried out under identical operational conditions employing both PPSU and blend membranes. The membranes were also subjected to the determination of molecular weight cut-off (MWCO) using different molecular weights of proteins. During trypsin ultrafiltration, PPSU/MWCNT and PPSU/FMWCNT membranes showed a slower flux decline rate than did the PPSU membrane.

  15. Bioseparation of papain from Carica papaya latex by precipitation of papain-poly (vinyl sulfonate) complexes.

    PubMed

    Braia, Mauricio; Ferrero, Maximiliano; Rocha, María Victoria; Loureiro, Dana; Tubio, Gisela; Romanini, Diana

    2013-09-01

    The formation of insoluble complexes between enzymes and polyelectrolytes is a suitable technique for isolating these biomolecules from natural sources, because it is a simple and rapid technique that allows the concentration of the protein. This technique can be used in most purification protocols at the beginning of the downstream process. The aim of this investigation is to isolate papain from Carica papaya latex by precipitation of insoluble complexes between this enzyme and poly (vinyl sulfonate). The papain-poly (vinyl sulfonate) complex was insoluble at pH lower than 6, with a PVS/PAP stoichiometric ratio of 1:279. Ionic strength affected the complex formation. The presence of the polymer increased the enzymatic activity and protected the enzyme from autodegradation. The optimal conditions for the formation of insoluble papain-polyelectrolyte complex formation were applied to C. papaya latex and a high recovery was obtained (around 86%) and a purification factor around 2. This method can be applied as an isolation method of papain from C. papaya latex or as a first step in a larger purification strategy.

  16. Ionic liquids composed of phosphonium cations and organophosphate, carboxylate, and sulfonate as lubricant antiwear additives

    SciTech Connect

    Zhou, Yan; Dyck, Jeffrey; Graham, Todd; Luo, Huimin; Leonard, Donovan N.; Qu, Jun

    2014-10-20

    Oil-soluble phosphonium-based ionic liquids (ILs) have recently been reported as potential ashless lubricant additives. This study is to expand the IL chemistry envelope and to achieve fundamental correlations between the ion structures and ILs’ physiochemical and tribological properties. Here we present eight ILs containing two different phosphonium cations and seven different anions from three groups: organophosphate, carboxylate, and sulfonate. The oil solubility of ILs seems largely governed by the IL molecule size and structure complexity. When used as oil additives, the ranking of effectiveness in wear protection for the anions are: organophosphate > carboxylate > sulfonate. All selected ILs outperformed a commercial ashless anti-wear additive. Surface characterization from the top and the cross-section revealed the nanostructures and compositions of the tribo-films formed by the ILs. Some fundamental insights were achieved: branched and long alkyls improve the IL’s oil solubility, anions of a phosphonium-phosphate IL contribute most phosphorus in the tribofilm, and carboxylate anions, though free of P, S, N, or halogen, can promote the formation of an anti-wear tribofilm.

  17. Methylation, Glucuronidation, and Sulfonation of Daphnetin in Human Hepatic Preparations In Vitro: Metabolic Profiling, Pathway Comparison, and Bioactivity Analysis.

    PubMed

    Liang, Si-Cheng; Xia, Yang-Liu; Hou, Jie; Ge, Guang-Bo; Zhang, Jiang-Wei; He, Yu-Qi; Wang, Jia-Yue; Qi, Xiao-Yi; Yang, Ling

    2016-02-01

    Our previous study demonstrated that daphnetin is subject to glucuronidation in vitro. However, daphnetin metabolism is still poorly documented. This study aimed to investigate daphnetin metabolism and its consequent effect on the bioactivity. Metabolic profiles obtained by human liver S9 fractions and human hepatocytes showed that daphnetin was metabolized by glucuronidation, sulfonation, and methylation to form 6 conjugates which were synthesized and identified as 7-O-glucuronide, 8-O-glucuronide, 7-O-sulfate and 8-O-sulfate, 8-O-methylate, and 7-O-suflo-8-O-methylate. Regioselective 8-O-methylation of daphnetin was investigated using in silico docking calculations, and the results suggested that a close proximity (2.03 Å) of 8-OH to the critical residue Lysine 144 might be the responsible mechanism. Compared with glucuronidation and sulfonation pathways, the methylation of daphnetin had a high clearance rate (470 μL/min/mg) in human liver S9 fractions and contributed to a large amount (37.3%) of the methyl-derived metabolites in human hepatocyte. Reaction phenotyping studies showed the major role of SULT1A1, -1A2, and -1A3 in daphnetin sulfonation, and soluble COMT in daphnetin 8-O-methylation. Of the metabolites, only 8-O-methyldaphnetin exhibited an inhibitory activity on lymphocyte proliferation comparable to that of daphnetin. In conclusion, methylation is a crucial pathway for daphnetin clearance and might be involved in pharmacologic actions of daphnetin in humans.

  18. Hydrogen bond cross-linked sulfonated poly(imino ether ether ketone) (PIEEK) for fuel cell membranes

    NASA Astrophysics Data System (ADS)

    Chang, Guanjun; Shang, Zhenfang; Yang, Li

    2015-05-01

    A new diamine monomer, 3,3‧-dihydroxydiphenylamine, is prepared by the palladium catalyzed C-N coupling reaction and the following reduction reaction of 3-bromoanisole and m-anisidine. A series of novel hydrogen bond cross-linked sulfonated poly(imino ether ether ketone) (SPIEEK) are obtained by the copolymerization of sodium 5,5‧-carbonylbis(2-fluorobenzene sulfonate), 4,4‧-difluorobenzophenone with 3,3‧-dihydroxydiphenylamine. The structures of resulting polymers are characterized by means of FT-IR, 1H NMR spectroscopy, and elemental analysis; the results show an agreement with the proposed structure. The resulting SPIEEK membranes display much better resistance to swelling than these without imino groups due to the strong interchain interaction through imino and sulfonic acid groups. The SPIEEK-60 and SPIEEK-80 membrane show the proton conductivity of 0.118 and 0.154 S cm-1 at 80 °C which is higher than Nafion 117 (0.082 S cm-1 at 80 °C). Moreover, the SPIEEK membranes exhibit good mechanical properties and lower methanol permeability due to the hydrogen bondings between the polymer chains.

  19. Penicillanic acid sulfone: interaction with RTEM beta-lactamase from Escherichia coli at different pH values.

    PubMed

    Kemal, C; Knowles, J R

    1981-06-23

    The interaction of the sulfone of penicillanic acid with the TEM-2 beta-lactamase from Escherichia coli has been investigated as a function of pH between pH 7.0 and 9.6. The first-formed acyl-enzyme suffers one of three fates: deacylation, tautomerization to a bound enamine that transiently inhibited the enzyme, and a process (possibly transimination) that leads to enzyme inactivation. The observed changes in ultraviolet absorbance are consistent with the initially observed product of deacylation being the enamine tautomer (4) of the imine from malonsemialdehyde and penicillamine sulfinate. The same enamine can be generated nonenzymically from the sulfone at high pH. The transiently inhibited enzyme appears to be the same enamine attached to the enzyme by an ester linkage. The rather complex kinetic behavior can be deconvuluted by exploiting the effect of pH on the partitioning of the acyl-enzyme between deacylation and the transiently inhibited form of the enzyme. The pathways followed by penicillanic acid sulfone provide a model for the behavior of a number of other reagents that inactivate the beta-lactamase.

  20. Synthesis and solid-state NMR characterization of cubic mesoporous silica SBA-1 functionalized with sulfonic acid groups.

    PubMed

    Tsai, Hui-Hsu Gavin; Chiu, Po-Jui; Jheng, Guang-Liang; Ting, Chun-Chiang; Pan, Yu-Chi; Kao, Hsien-Ming

    2011-07-01

    Well-ordered cubic mesoporous silicas SBA-1 functionalized with sulfonic acid groups have been synthesized through in situ oxidation of mercaptopropyl groups with H(2)O(2) via co-condensation of tetraethoxysilane (TEOS) and 3-mercaptopropyltrimethoxysilane (MPTMS) templated by cetyltriethylammonium bromide (CTEABr) under strong acidic conditions. Various synthesis parameters such as the amounts of H(2)O(2) and MPTMS on the structural ordering of the resultant materials were systematically investigated. The materials thus obtained were characterized by a variety of techniques including powder X-ray diffraction (XRD), multinuclear solid-state Nuclear Magnetic Resonance (NMR) spectroscopy, (29)Si{(1)H} 2D HETCOR (heteronuclear correlation) NMR spectroscopy, thermogravimetric analysis (TGA), and nitrogen sorption measurements. By using (13)C CPMAS NMR technique, the status of the incorporated thiol groups and their transformation to sulfonic acid groups can be monitored and, as an extension, to define the optimum conditions to be used for the oxidation reaction to be quantitative. In particular, (29)Si{(1)H} 2D HETCOR NMR revealed that the protons in sulfonic acid groups are in close proximity to the silanol Q(3) species, but not close enough to form a hydrogen bond.

  1. Polyether sulfone/hydroxyapatite mixed matrix membranes for protein purification

    NASA Astrophysics Data System (ADS)

    Sun, Junfen; Wu, Lishun

    2014-07-01

    This work proposes a novel approach for protein purification from solution using mixed matrix membranes (MMMs) comprising of hydroxyapatite (HAP) inside polyether sulfone (PES) matrix. The influence of HAP particle loading on membrane morphology is studied. The MMMs are further characterized concerning permeability and adsorption capacity. The MMMs show purification of protein via both diffusion as well as adsorption, and show the potential of using MMMs for improvements in protein purification techniques. The bovine serum albumin (BSA) was used as a model protein. The properties and structures of MMMs prepared by immersion phase separation process were characterized by pure water flux, BSA adsorption and scanning electron microscopy (SEM).

  2. Sulfone/Ester Polymers Containing Pendent Ethynyl Groups

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M.; Jensen, B. J.

    1986-01-01

    Two processes make high-performance polymers resistant to solvents, without compromising mechanical characteristics. Polymers show improved solvent resistance while retaining high toughness, thermoformability, and mechanical performance. Multistep process involves conversion of pendent bromo group to ethynyl group, while direct process involves reacting hydroxy-terminated sulfone oligomers or polymers with stoichiometric amount of 5-(4-ethynylphenoxy) isophthaloyl chloride. Applications for new polymers include adhesives, composite resin matrices, moldings, ultrafiltration membranes, protective coatings, and such electrical insulators as thin films for microelectronic circuitry.

  3. Absorption of nitrogen oxides by sulfoxides and sulfones

    SciTech Connect

    Bikbaeva, G.G.; Isyangil'dina, A.Kh.; Baranovskaya, E.M.; Nikitin, Yu.E.

    1986-10-10

    Petroleum sulfoxides (PSO) have high sorption capacity for NO/sub 2/. In view of their comparative availability and low cost, PSO may be of practical interest as absorbents for nitrogen oxides. At the same time, the properties of adducts formed by sulfoxides, both individual and from petroleum, with nitrogen oxides have been studies very little. In this work the methods of IR and UV spectroscopy were used for studying complex formation of nitrogen oxides with sulfoxides, and also with sulfones, obtained by oxidation of sulfoxides.

  4. Effect of water on overbased sulfonate engine oil additives.

    PubMed

    Tavacoli, J W; Dowding, P J; Steytler, D C; Barnes, D J; Routh, A F

    2008-04-15

    The presence and effect of water on calcium carbonate nanoparticles used in engine additives, stabilized with a sulfonate surfactant, is investigated using small-angle neutron scattering, dynamic light scattering, Fourier transform infrared spectroscopy, and rheometry. These techniques provide complementary data that suggests the formation of a layer of water around the core of the particles ensuring continued colloidal stability yet increasing the dispersion viscosity. Through the use of small-angle neutron scattering, the dimensions of this layer have been quantified to effectively one or two water molecules in thickness. The lack of a significant electrostatic repulsion is evidence that the water layer is insufficient to cause major dissociation of surface ions.

  5. Rh(III)-catalyzed synthesis of sultones through C-H activation directed by a sulfonic acid group.

    PubMed

    Qi, Zisong; Wang, Mei; Li, Xingwei

    2014-09-04

    A new rhodium-catalyzed synthesis of sultones via the oxidative coupling of sulfonic acids with internal alkynes is described. The reaction proceeds via aryl C-H activation assisted by a sulfonic acid group.

  6. Sulfones and sulfonamides in dermatology today.

    PubMed

    Lang, P G

    1979-12-01

    Although dapsone and sulfapyridine have been used for years in dermatology, there has not always been a clear understanding of how these agents work. Recent investigation, however, has shed new light on thes agents which now allows a more rational approach to their use. This review is an attempt to familiarize the clinician with how these agents work, in what disease states they are effective, how to administer them, what adverse effects may occur, and how to monitor the patient to detect these adverse effects.

  7. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  8. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  9. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  10. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  11. 40 CFR 721.10045 - Diazotized substituted heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (generic). 721.10045... derivative, nickel complex, alkaline salt (generic). (a) Chemical substance and significant new uses subject... heteromonocycle coupled with naphthalene sulfonic acid derivative, nickel complex, alkaline salt (PMN P-02-737)...

  12. Colonic necrosis due to calcium polystyrene sulfonate (Kalimate) not suspended in sorbitol.

    PubMed

    Castillo-Cejas, María Dolores; de-Torres-Ramírez, Inés; Alonso-Cotoner, Carmen

    2013-04-01

    Cation-exchange resins are used in the management of hyperkalemia, particularly in patients with end-stage renal disease. These resins were associated with gastrointestinal tract lesions, especially sodium polystyrene sulfonate (Kayexalate) mixed with sorbitol. We present a case of colonic necrosis after the administration of calcium polystyrene sulfonate (Kalimate) not suspended in sorbitol.

  13. Cationic and radical intermediates in the acid photorelease from aryl sulfonates and phosphates.

    PubMed

    Terpolilli, Marco; Merli, Daniele; Protti, Stefano; Dichiarante, Valentina; Fagnoni, Maurizio; Albini, Angelo

    2011-01-01

    The irradiation of a series of phenyl sulfonates and phosphates leads to the quantitative release of acidity with a reasonable quantum yield (≈0.2). Products characterization, ion chromatography analysis and potentiometric titration are consistent with the intervening of two different paths in this reaction, viz. cationic with phosphates and (mainly) radical with sulfonates.

  14. Coating of Sulfonic Silica onto Magnetite from Marina Beach Iron sand, Semarang, Indonesia

    NASA Astrophysics Data System (ADS)

    Azmiyawati, C.; Suyati, L.; Taslimah; Anggraeni, R. D.

    2017-02-01

    The mineral iron oxide is the main component of sand iron that are abundant in nature. Mineral iron oxide not yet widely applied into more useful products. The main component of iron ore is magnetite. Magnetite can be used as a basic ingredient in the manufacture of magnetite-modified silica adsorbent sulfonate. In this research, the adsorbent made from sulfonic functionalized silica-coated magnetic particle has been successfully produced, with the magnetite was obtained from iron sand at Marina Beach, Semarang Indonesia. This adsorbent was then used as a metal ion preconcentration media. From the research that it was found that the sulfonic has been bound to the silica marked by the emergence of element S on EDX. Whilst, the evidence that silica has coated on the magnetite could be seen from the SEM images which showed the morphology of sulfonic functionalized silica-coated magnetic particles were larger than the sulfonic functionalized silica without magnetite. From the DSC results showed that the addition of magnetite on sulfonic functionalized silica did not change the heat resistance of the sulfonic functionalized silica. Based on the XRD patterns show that magnetite sulfonate silica was formed.

  15. Synthesis and Structure-Property Relationships of Poly(sulfone)s for Anion Exchange Membranes

    SciTech Connect

    Yan, JL; Moore, HD; Hibbs, MR; Hickner, MA

    2013-10-05

    Membranes based on cationic polymers that conduct anions are important for enabling alkaline membrane fuel cells and other solid-state electrochemical devices that operate at high pH. Anion exchange membranes with poly(arylene ether sulfone) backbones are demonstrated by two routes: chloromethylation of commercially available poly(sulfone)s or radical bromination of benzylmethyl moieties in poly(sulfone)s containing tetramethylbisphenol A monomer residues. Polymers with tethered trimethylbenzyl ammonium moieties resulted from conversion of the halomethyl groups by quaternization with trimethyl amine. The water uptake of the chloromethylated polymers was dependent on the type of poly(sulfone) backbone for a given IEC. Bisphenol A-based Udel (R) poly(sulfone) membranes swelled in water to a large extent while membranes from biphenol-based Radel (R) poly(sulfone), a stiffer backbone than Udel, only showed moderate water uptake. The water uptake of cationic poly(sulfone)s was further reduced by synthesizing tetramethylbisphenol A and 4,4-biphenol-containing poly(sulfone) copolymers where the ionic groups were clustered on the tetramethylbisphenol A residues. The conductivity of all samples scaled with the bulk water uptake. The hydration number of the membranes could be increased by casting membranes from the ionic form polymers versus converting the halomethyl form cast polymers to ionic form in the solid state. (c) 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1790-1798, 2013

  16. Bis-sulfonic acid ionic liquids for the conversion of fructose to 5-hydroxymethyl-2-furfural.

    PubMed

    Sim, Sang Eun; Kwon, Sunjeong; Koo, Sangho

    2012-10-31

    Homogenous bis-sulfonic acid ionic liquids (1 mol equiv.) in DMSO (10 mol equiv.) at 100 °C efficiently mediated the conversion of D-fructose into 5-hydroxymethyl-2-furfural in 75% isolated yield, which was roughly a 10% increment compared to the case of the mono-sulfonic acid ionic liquids.

  17. 40 CFR 721.2565 - Alkylated sulfonated diphenyl oxide, alkali and amine salts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., alkali and amine salts. 721.2565 Section 721.2565 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.2565 Alkylated sulfonated diphenyl oxide, alkali and... substances identified as alkylated sulfonated diphenyl oxide, alkali salt (PMN P-93-352) and...

  18. 40 CFR 721.2565 - Alkylated sulfonated diphenyl oxide, alkali and amine salts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., alkali and amine salts. 721.2565 Section 721.2565 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.2565 Alkylated sulfonated diphenyl oxide, alkali and... substances identified as alkylated sulfonated diphenyl oxide, alkali salt (PMN P-93-352) and...

  19. 40 CFR 721.2565 - Alkylated sulfonated diphenyl oxide, alkali and amine salts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., alkali and amine salts. 721.2565 Section 721.2565 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.2565 Alkylated sulfonated diphenyl oxide, alkali and... substances identified as alkylated sulfonated diphenyl oxide, alkali salt (PMN P-93-352) and...

  20. Designer ionic liquid crystals based on congruently shaped guanidinium sulfonates.

    PubMed

    Butschies, Martin; Frey, Wolfgang; Laschat, Sabine

    2012-03-05

    Ionic liquid crystals are mesogenic compounds that consist of cations and anions, usually rod-like cations and spherical anions. Herein we report a new method for the synthesis of ionic liquid crystals by using cations and anions of the same molecular shape with oppositely charged head groups. Thus, 4-alkoxyphenylpentamethylguanidinium 4-alkoxyphenylsulfonate ion pairs have been synthesised. 4-Alkoxyphenylpentamethylguanidinium iodides were also prepared to determine the influence of congruently shaped anions, in comparison with their spherical counterparts, on mesophase behaviour, which was investigated by differential scanning calorimetry (DSC), polarising optical microscopy (POM) and X-ray diffraction (XRD). All the liquid crystalline salts exhibit smectic A mesophases with strongly interdigitated bilayer structures. The guanidinium sulfonate ion pairs show mesomorphic properties from shorter alkyl chain lengths (≥C(9)) and lower melting points (≈10 K), whereas the corresponding guanidinium iodides are liquid crystalline for longer alkyl chain lengths (≥C(14)). For chains with ≥C(18), however, the mesophase range decreases for the sulfonate ion pairs, but not for the iodide salts.

  1. Aryl sulfonates as neutral photoacid generators (PAGs) for EUV lithography

    NASA Astrophysics Data System (ADS)

    Sulc, Robert; Blackwell, James M.; Younkin, Todd R.; Putna, E. Steve; Esswein, Katherine; DiPasquale, Antonio G.; Callahan, Ryan; Tsubaki, Hideaki; Tsuchihashi, Tooru

    2009-03-01

    EUV lithography (EUVL) is a leading candidate for printing sub-32 nm hp patterns. In order for EUVL to be commercially viable at these dimensions, a continuous evolution of the photoresist material set is required to simultaneously meet the aggressive specifications for resolution, resist sensitivity, LWR, and outgassing rate. Alternative PAG designs, especially if tailored for EUVL, may aid in the formation of a material set that helps achieve these aggressive targets. We describe the preparation, characterization, and lithographic evaluation of aryl sulfonates as non-ionic or neutral photoacid generators (PAGs) for EUVL. Full lithographic characterization is reported for our first generation resist formulation using compound H, MAP-1H-2.5. It is benchmarked against MAP-1P-5.0, which contains the well-known sulfonium PAG, triphenylsulfonium triflate (compound P). Z-factor analysis indicates nZ32 = 81.4 and 16.8 respectively, indicating that our first generation aryl sulfonate formulations require about 4.8x improvement to match the results achieved with a model onium PAG. Improving the acid generation efficiency and use of the generated byproducts is key to the continued optimization of this class of PAGs. To that end, we believe EI-MS fragmentation patterns and molecular simulations can be used to understand and optimize the nature and efficiency of electron-induced PAG fragmentation.

  2. Bacterial communities degrading amino- and hydroxynaphthalene-2-sulfonates.

    PubMed Central

    Nörtemann, B; Baumgarten, J; Rast, H G; Knackmuss, H J

    1986-01-01

    A 6-aminonaphthalene-2-sulfonic acid (6A2NS)-degrading mixed bacterial community was isolated from a sample of river Elbe water. The complete degradation of this xenobiotic compound may be described by a mutualistic interaction of two Pseudomonas strains isolated from this culture. One strain, BN6, could also grow on 6A2NS in monoculture, however, with accumulation of black polymers. This organism effected the initial conversion of 6A2NS into 5-aminosalicylate (5AS) through regioselective attack of the naphthalene skeleton in the 1,2-position. 5AS was totally degraded by another member of the community, strain BN9. After prolonged adaptation of strain BN6 to growth on 6A2NS, this organism readily converted all naphthalene-2-sulfonates with OH- or NH2-substituents in the 5-, 6-, 7-, or 8-position. The corresponding hydroxy- or aminosalicylates were excreted in stoichiometric amounts, with the exception that the metabolite from 5A2NS oxidation was not identical with 6AS. Images PMID:3789715

  3. 40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection of... MANUFACTURING POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory § 417.140 Applicability; description of the neutralization of sulfuric acid esters and sulfonic...

  4. 40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection of... MANUFACTURING POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory § 417.140 Applicability; description of the neutralization of sulfuric acid esters and sulfonic...

  5. 40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection of... MANUFACTURING POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory § 417.140 Applicability; description of the neutralization of sulfuric acid esters and sulfonic...

  6. 40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection of... MANUFACTURING POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory § 417.140 Applicability; description of the neutralization of sulfuric acid esters and sulfonic...

  7. 40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection of... MANUFACTURING POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory § 417.140 Applicability; description of the neutralization of sulfuric acid esters and sulfonic...

  8. Effect of ion interactions on the IR spectrum of benzenesulfonate ion. Restoration of sulfonate ion symmetry in sodium benzenesulfonate dimer

    NASA Astrophysics Data System (ADS)

    Shishlov, N. M.; Khursan, S. L.

    2016-11-01

    Literature data concerning the assignment of IR spectra of benzenesulfonate salts that serve as model compounds for aromatic sulfonate-containing ionomers and polyelectrolytes have been analyzed. The structures and IR spectra of free benzenesulfonate ion and its potassium and sodium salts have been calculated in B3LYP/6-311G(d,p) approximation. The bidentate coordination of counter-ions is energetically favorable for isolated ion pairs. In this coordination, the symmetry of sulfonate ion changes noticeably, which manifests itself as strong splitting of calculated vibrational modes of asymmetric stretching vibrations of Ssbnd O bonds, Δνas(SO3) = 154 cm-1 (K) and 180 cm-1 (Na). For sodium benzenesulfonate it is thermodynamically favorable to form a dimer (ΔG° = -37.6 kcal/mol) in which the joint effects of monodentate and bidentate coordinated Na cations result in equalization of Ssbnd O bond lengths and thus a considerable restoration of C3V symmetry of the sulfonate ion. The IR spectrum of the dimer in which Δνas(SO3) splitting is considerably smaller much better matches the experimental spectrum than the spectrum of an isolated ion pair. The major absorption bands in the IR spectrum of sodium benzenesulfonate have been assigned to theoretical vibrational modes of the dimer and, based on visualization of modes, to vibrations of certain bonds in the anion. In particular, the bands at 1200 and 1186 cm-1 have been assigned to νas(SO3), that at 1049 cm-1 to νs(SO3), and those at 628 and 572 cm-1 to δ(oop)s(SO3), and δ(ip)as(SO3), respectively. The strong effect of sulfonate ion environment on the positions of the absorption bands of stretching vibrations of Ssbnd O bonds makes it necessary to obtain data on exact structures of ion clusters for reliable assignment of absorption bands in experimental IR spectra of real sulfonate-containing systems.

  9. A new strategy for the synthesis of taurine derivatives using the 'safety-catch' principle for the protection of sulfonic acids.

    PubMed

    Seeberger, Sonja; Griffin, Roger J; Hardcastle, Ian R; Golding, Bernard T

    2007-01-07

    The safety-catch principle has been applied for the development of a new method for protecting sulfonic acids. 2,2-Dimethylsuccinic acid was reduced to 2,2-dimethylbutane-1,4-diol, which was selectively silylated to give 4-(tert-butyldiphenylsilanyloxy)-2,2-dimethylbutan-1-ol. Reaction of the latter compound with 2-chloroethanesulfonyl chloride in the presence of triethylamine afforded 4-(tert-butyldiphenylsilyloxy)-2,2-dimethylbutyl ethenesulfonate directly. The ethenesulfonate underwent Michael-type addition with secondary amines to give protected derivatives of taurine (2-aminoethanesulfonic acid). Deprotection was achieved on treatment with tetrabutylammonium fluoride, whereby cleavage of the silicon-oxygen bond led to an intermediate alkoxide that immediately cyclised to 2,2-dimethyltetrahydrofuran with liberation of a sulfonate. Pure sulfonic acids were obtained from the crude product by ion exchange chromatography on a strongly basic resin, which was eluted with aqueous acetic acid. The method developed should be generally applicable to the protection of sulfonic acids and is amenable to a multiparallel format.

  10. A simple LC-MS/MS method to determine plasma and cerebrospinal fluid levels of albendazole metabolites (albendazole sulfoxide and albendazole sulfone) in patients with neurocysticercosis.

    PubMed

    González-Hernández, Iliana; Ruiz-Olmedo, María Isabel; Cárdenas, Graciela; Jung-Cook, Helgi

    2012-02-01

    The development and validation of an LC-MS/MS method for the simultaneous determination of albendazole metabolites (albendazole sulfoxide and albendazole sulfone) in human plasma are described. Samples of 200 μL were extracted with ether-dichloromethane-chloroform (60:30:10, v/v/v). The chromatographic separation was performed using a C(18) column with methanol-formic acid 20 mmol/L (70:30) as the mobile phase. The method was linear in a range of 20-5000 ng/mL for albendazole sulfoxide and 10-1500 ng/mL for albendazole sulfone. For both analytes the method was precise (RSD < 12%) and accurate (RE <7%) with high recovery (>90%). The method was successfully applied to determine the plasma and cerebrospinal fluid levels of albendazole sulfoxide and albendazole sulfone in patients with subarachnoidal neurocysticercosis who received albendazole at 30 mg/kg per day for 7 days. This LC-MS/MS method yielded a quick, simple and reliable protocol for determining albendazole sulfoxide and albendazole sulfone concentrations in plasma and cerebrospinal fluid samples and is applicable to therapeutic monitoring.

  11. Sulfonated polyphosphazene-based membranes for use in direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Carter, Roy Lee

    Novel crosslinked and sulfonated poly[bis(3-methylphenoxy)phosphazene] blended proton exchange membranes were fabricated for use as the solid polymer electrolyte in a direct methanol fuel cell. Three polymers, polybenzimidazole, polyacrylonitrile and polyvinylidene fluoride-co-polyhexafluoropropylene were found to be compatible for blending with sulfonated polyphosphazene. A combination of blending and crosslinking was shown to be an effective method of producing durable, low water swelling films with acceptable proton conductivity. A novel tracer-diffusion 1H NMR method was developed and used to measure the mutual diffusion of methanol in non-crosslinked and crosslinked membranes composed of sulfonated polyphosphazene. The technique measures the growth of a solute NMR signal in the bulk (external) solution as it diffuses out of a thin film membrane. The transient increase in methanol peak height during analyte (methanol) desorption was fitted to a simple theoretical diffusion model using the methanol diffusion coefficient as an adjustable parameter. This method was found to be fast, reproducible, and accurate to within about +/-20%. Diffusion coefficients at 25°C were in the range of 1.0 x 10-8 cm2/s to 4.0 x 10-7 cm2/s for methanol concentrations of 1.0--5.0 M and were significantly smaller than those reported for a NafionRTM perfluorosulfonic acid membrane. Direct liquid methanol fuel cell tests were performed with membrane electrode assemblies (MEAs) fabricated with polyphosphazene-based proton-exchange membranes. MEAs worked best when high ion-exchange capacity (high conductivity) polyphosphazene membrane contacted the electrodes, in which case the fuel cell power output was nearly the same as that with Nafion 117 (for current densities ≤0.15 A/cm2), but the methanol crossover was three times lower than that of Nafion. The electrochemical performance of single-membrane MEAs with low conductivity S-POP/PAN films was poor, although the methanol crossover was

  12. Effect of the incorporation of sulfonated chitosan/sulfonated graphene oxide on the proton conductivity of chitosan membranes

    NASA Astrophysics Data System (ADS)

    Shirdast, Abbas; Sharif, Alireza; Abdollahi, Mahdi

    2016-02-01

    Chitosan biopolymer (CS) has been attracting considerable interest as polymer electrolyte in fuel cells. However, proton conductivity of chitosan is low and it is necessary to enhance its conductivity. In this work, 10 wt% sulfonated chitosan (SCS) and different amounts of sulfonated graphene oxide (SGO) nanosheets are incorporated into a chitosan membrane to investigate their effects on the electrochemical properties of the membrane. The proton conductivity and methanol permeability tests conducted on the CS/SCS/SGO membranes show that the conductivity is increased by 454%, the permeability is reduced by 23% and hence the selectivity is increased by 650%, relative to the neat chitosan, at SGO content of 5 wt%. Furthermore, combined addition of SCS and SGO to chitosan causes much more proton conductivity enhancement than the individual additives due to the synergistic effect of SCS and SGO. The observed synergistic effect reveals the importance of the chemical functionality of chitosan and nanofillers in the formation of ionic cluster domains with enhanced size within the membranes for proton transport. Finally, a Nernst-Planck based model is applied to the experimental proton conductivity data in order to shed more light on the role of GOs in the proton conductivity mechanism of chitosan.

  13. Crystal structures of three N-(aryl-sulfon-yl)-4-fluoro-benzamides.

    PubMed

    Suchetan, P A; Naveen, S; Lokanath, N K; Srivishnu, K S; Supriya, G M; Lakshmikantha, H N

    2016-04-01

    The crystal structures of three N-aryl-sulfonyl-4-fluoro-benzamides, namely 4-fluoro-N-(2-methyl-phenyl-sulfon-yl)benzamide, C14H12FNO3S, (I), N-(2-chloro-phenyl-sulfon-yl)-4-fluorobenzamide, C13H9ClFNO3S, (II), and N-(4-chloro-phenyl-sulfon-yl)-4-fluoro-benzamide monohydrate, C13H9ClFNO3S·H2O, (III), are described and compared with related structures. The asymmetric unit of (I) contains two independent mol-ecules (A and B), while that of (II) contains just one mol-ecule, and that of (III) contains a mol-ecule of water in addition to one main mol-ecule. The dihedral angle between the benzene rings is 82.83 (11)° in mol-ecule A and 85.01 (10)° in mol-ecule B of (I), compared to 89.91 (10)° in (II) and 81.82 (11)° in (III). The crystal structure of (I) features strong N-H⋯O hydrogen bonds between the A and B mol-ecules, resulting in an R 4 (4)(16) tetra-meric unit. These tetra-meric units are connected into sheets in the bc plane by various C-H⋯O inter-actions, and adjacent sheets are further inter-linked via C-H⋯πar-yl inter-actions, forming a three-dimensional architecture. The crystal structure is further stabilized by πar-yl-πar-yl and S=O⋯πar-yl inter-actions. In the crystal of (II), mol-ecules are connected into R 2 (2)(8) and R 2 (2)(14) dimers via N-H⋯O hydrogen bonds and C-H⋯O inter-actions, respectively; the dimers are further inter-connected via a weak C=O⋯πar-yl inter-action, leading to the formation of chains along [1-10]. In the crystal of (III), N-H⋯O and O-H⋯O hydrogen bonds involving both the main mol-ecule and the solvent water mol-ecule results in the formation of sheets parallel to the bc plane. The sheets are further connected by C-H⋯O inter-actions and weak C-Cl⋯πar-yl, C-F⋯πar-yl and S=O⋯πar-yl inter-actions, forming a three-dimensional architecture.

  14. DNA microarray mediated transcriptional profiling of Nitrosomonas europaea in response to linear alkylbenzene sulfonates.

    PubMed

    Urakawa, Hidetoshi; Matsumoto, Junpei; Inaba, Kazuho; Tsuneda, Satoshi

    2008-05-01

    Linear alkylbenzene sulfonates (LAS) constitute, quantitatively, the most important group of synthetic surfactants used today. We studied the gene expression of Nitrosomonas europaea in response to LAS using a DNA microarray because ammonia-oxidizers are thought to be more sensitive to LAS than other microorganisms. Our objective was to elucidate which genes are expressed for N. europaea in response to LAS exposure. Microarray analysis and real-time PCR assay revealed that c. 30 genes were significantly expressed after LAS exposure, in particular genes associated with energy production and conversion. Our findings demonstrate that physical disruption of membrane structures, which contain enzymes associated with energy production and conversion, might be an important explanation for the high sensitivity of N. europaea to LAS exposure.

  15. Identification of a new sulfonic acid metabolite of metolachlor in soil

    USGS Publications Warehouse

    Aga, D.S.; Thurman, E.M.; Yockel, M.E.; Zimmerman, L.R.; Williams, T.D.

    1996-01-01

    An ethanesulfonic acid metabolite of metolachlor (metolachlor ESA) was identified in soil-sample extracts by negative-ion, fast-atom bombardment mass spectrometry (FAB-MS) and FAB tandem mass spectrometry (FAB-MS/MS). Production fragments from MS/MS analysis of the deprotonated molecular ion of metolachlor ESA in the soil extract can be reconciled with the structure of the synthesized standard. The elemental compositions of the (M - H)- ions of the metolachlor ESA standard and the soil-sample extracts were confirmed by high-resolution mass spectrometry. A dissipation study revealed that metolachlor ESA is formed in soil under field conditions corresponding to a decrease in the concentration of the parent herbicide, metolachlor. The identification of the sulfonated metabolite of metolachlor suggests that the glutathione conjugation pathway is a common detoxification pathway shared by chloroacetanilide herbicides.

  16. The selective determination of sulfates, sulfonates, and phosphates in urine by capillary electrophoresis/mass spectrometry.

    PubMed

    Bunz, Svenja-Catharina; Neusüß, Christian

    2013-01-01

    Metabolite identification and metabolite profiling are of major importance in the pharmaceutical and clinical context. However, anions of biological relevance such as sulfates, sulfonates, and phosphates are rarely included in common techniques for metabolite studies. In this protocol, we demonstrate a unique method to selectively determine these anions. The method comprises a capillary electrophoresis separation using an acidic background electrolyte (pH ≤ 2) and anodic detection by mass spectrometry via negative electrospray ionization. In this way, only anions of strong acids like sulfates are determined. The selectivity for sulfur-containing species is proved based on the specific isotopic ratios. In conjunction with the accurate mass from the time-of-flight mass spectrometer, the presented method is well suited for clinical and pharmaceutical applications to identify possible metabolites and to quantify known metabolites.

  17. Anaerobic degradation pathway of linear Alkylbenzene sulfonates (LAS) in sulfate-reducing marine sediments.

    PubMed

    Lara-Martín, Pablo A; Gómez-Parra, Abelardo; Sanz, José Luis; González-Mazo, Eduardo

    2010-03-01

    Linear alkylbenzene sulfonates (LAS) are among the principal synthetic surfactants used worldwide. Their presence in the environment has been reported in a significant number of studies, and it has been generally assumed that LAS are not biotransformed in the absence of oxygen. However, laboratory experiments performed by our group using anoxic marine sediments have reported LAS degradation percentages that can reach up to 79% in 165 days. Here, we show for the first time the initial reaction metabolites (generated via fumarate addition to the LAS molecules), their biotransformation into sulfophenyl carboxylic acids (SPC), and the progressive degradation of these by successive beta-oxidation reactions. Advanced mass spectrometry has been used to carry out the identification of these compounds. This is the first time that an anaerobic degradation pathway for LAS is described, and these results represent a significant advance in understanding the final fate of these and other similar compounds in anoxic environments.

  18. Chemical doping of MoS2 multilayer by p-toluene sulfonic acid

    PubMed Central

    Andleeb, Shaista; Kumar Singh, Arun; Eom, Jonghwa

    2015-01-01

    We report the tailoring of the electrical properties of mechanically exfoliated multilayer (ML) molybdenum disulfide (MoS2) by chemical doping. Electrical charge transport and Raman spectroscopy measurements revealed that the p-toluene sulfonic acid (PTSA) imposes n-doping in ML MoS2. The shift of threshold voltage for ML MoS2 transistor was analyzed as a function of reaction time. The threshold voltage shifted toward more negative gate voltages with increasing reaction time, which indicates an n-type doping effect. The shift of the Raman peak positions was also analyzed as a function of reaction time. PTSA treatment improved the field-effect mobility by a factor of ~4 without degrading the electrical characteristics of MoS2 devices. PMID:27877810

  19. Reactivity and fate of secondary alkane sulfonates (SAS) in marine sediments.

    PubMed

    Baena-Nogueras, Rosa María; Rojas-Ojeda, Patricia; Sanz, José Luis; González-Mazo, Eduardo; Lara-Martín, Pablo A

    2014-06-01

    This research is focused on secondary alkane sulfonates (SAS), anionic surfactants widely used in household applications that access aquatic environments mainly via sewage discharges. We studied their sorption capacity and anaerobic degradation in marine sediments, providing the first data available on this topic. SAS partition coefficients increased towards those homologues having longer alkyl chains (from up to 141 L kg(-1) for C14 to up to 1753 L kg(-1) for C17), which were those less susceptible to undergo biodegradation. Overall, SAS removal percentages reached up to 98% after 166 days of incubation using anoxic sediments. The degradation pathway consisted on the formation of sulfocarboxylic acids after an initial fumarate attack of the alkyl chain and successive β-oxidations. This is the first study showing that SAS can be degraded in absence of oxygen, so this new information should be taken into account for future environmental risk assessments on these chemicals.

  20. Transfer of perfluorooctane sulfonic acid (PFOS) from contaminated feed to dairy milk.

    PubMed

    van Asselt, E D; Kowalczyk, J; van Eijkeren, J C H; Zeilmaker, M J; Ehlers, S; Fürst, P; Lahrssen-Wiederholt, M; van der Fels-Klerx, H J

    2013-11-15

    Dietary intake is the predominant route for human exposure to perfluorooctane sulfonic acid (PFOS). Single pollution events may thus affect human exposure if polluted ground and water is used to produce animal feed or food. In this study, a physiologically based pharmacokinetic (PBPK-) model is derived that describes the uptake of PFOS from contaminated feed by cows and its subsequent elimination through the cows' milk. Parameter values of the model were estimated by fitting to experimental data of a cow feeding trial. Model calculations showed that almost all PFOS ingested is excreted through the cows' milk. The elimination rate, however, was low as the estimated half-life in the cow was 56days and it may, thus, take a long time after an initial pollution event to produce PFOS-free milk. The derived model can be used to estimate the transfer of PFOS through the dairy food chain and can be used for comparison of various contamination routes.

  1. Assessment of perfluorooctanoic acid and perfluorooctane sulfonate in surface water - Tamil Nadu, India.

    PubMed

    Sunantha, Ganesan; Vasudevan, Namasivayam

    2016-08-15

    As an emerging class of environmentally persistent organic pollutants, perfluorinated compounds (PFCs), particularly perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS); have been universally found in the environment. Wastewater and untreated effluents are likely the major causes for the accumulation of PFCs in surface water. There are very few reports on the contamination of PFCs in the developing countries, particularly in India. This study reports the quantitative analysis of PFOA and PFOS in Noyyal, Cauvery, and also lakes in and around Chennai, using Ultra-Fast liquid chromatograph. The concentration of PFOA and PFOS ranged from 4 to 93ng/L and 3 to 29ng/L, respectively. The concentration of PFOS was below detectable limit in Cauvery River. A reliable concentration of PFOA was recorded at all sites of River Cauvery (5ng/L). The present study could be useful for the assessment of future monitoring programs of PFOA and PFOS in the surface water.

  2. Effect of linear alkyl benzene sulfonate on germination of spores of the aquatic fern Ceratopteris thalictroides

    SciTech Connect

    Singh, J.; Devi, S. )

    1989-07-01

    Validity of fern spore germination bioassays for the effects of environmental pollution was established by many researchers. Some workers studied the phytotoxicity of linear alkyl benzene sulfonate (LAS) on the spores of Diplazium esculentum and observed that LAS levels above 0.001% are toxic to fern spores. Water pollution due to synthetic detergents has been increasing continuously during the last few years due to their extensive use in domestic life, agriculture and industry. These detergents are among the most common pollutants responsible for water pollution. In view of this fact, the phytotoxicity of LAS on germination of an aquatic fern Ceratopteris thalictroides spores was studied. However, in these studies, only germination pattern was taken as index and no observations were made on the developmental stages.

  3. Layered solids based on second-sphere coordination interactions: synthesis, spectroscopic characterization, crystal structure and packing of two copper(II) naphthalene-2-sulfonates

    NASA Astrophysics Data System (ADS)

    Sharma, Raj Pal; Sharma, Rajni; Bala, Ritu; Rychlewska, Urszula; Warżajtis, Beata

    2005-03-01

    [Cu(H 2O) 6](C 10H 7SO 3) 21 was obtained from reaction of CuCO 3·Cu(OH) 2 and naphthalene-2-sulphonic acid in aqueous medium in 1:4 molar ratio. It crystallizes in the monoclinic space group P2 1/ n with a=7.0582(3) Å, b=6.2666(3) Å, and c=27.1420(10) Å, β=92.678(4)°, Z=2. The structure was determined from 1986 observed reflections and refined to R=0.033. When ethylenediamine was added to hexaaquacopper(II) naphthalene-2-sulfonate dissolved in water, [Cu(en) 2(H 2O) 2](C 10H 7SO 3) 22 was obtained which crystallizes in the triclinic space group P1¯ with a=7.1491(5) Å, b=7.1949(5) Å, and c=14.6500(10) Å, α=99.025(6)°, β=98.976(6)°, and γ=104.262(6)°, Z=1. The structure was determined from 2296 observed reflections and refined to R=0.0313. X-ray structure determination of 1 revealed an ionic structure consisting of [Cu(H 2O) 6] +2 and two naphthalene-2-sulfonate anions while that of 2 contains [Cu(en) 2(H 2O) 2] 2+ cation and two naphthalene-2-sulfonate anions. Characteristic for the studied crystals is the alternated-layer arrangement of complex cations and naphthalene-2-sulfonate anions, linked together via hydrogen bonding, and the presence of a particularly robust R22(8) hydrogen-bonding motif that joins the complex cation with two oxygen atoms of the same sulfonate group. Elemental analyses, IR, UV/vis spectroscopic studies are consistent with the structures revealed by X-ray structure determination.

  4. Development of a novel sulfonate ester-based prodrug strategy.

    PubMed

    Hanaya, Kengo; Yoshioka, Shohei; Ariyasu, Shinya; Aoki, Shin; Shoji, Mitsuru; Sugai, Takeshi

    2016-01-15

    A self-immolative γ-aminopropylsulfonate linker was investigated for use in the development of prodrugs that are reactive to various chemical or biological stimuli. To demonstrate their utility, a leucine-conjugated prodrug of 5-chloroquinolin-8-ol (5-Cl-8-HQ), which is a potent inhibitor against aminopeptidase from Aeromonas proteolytica (AAP), was synthesized. The sulfonate prodrug was considerably stable under physiological conditions, with only enzyme-mediated hydrolysis of leucine triggering the subsequent intramolecular cyclization to simultaneously release 5-Cl-8-HQ and form γ-sultam. It was also confirmed that this γ-aminopropylsulfonate linker was applicable for prodrugs of not only 8-HQ derivatives but also other drugs bearing a phenolic hydroxy group.

  5. Phase behavior of 1-alkylpyridinium octane-1-sulfonates. effect of the 1-alkylpyridinium counterion size.

    PubMed

    Persson, Gerd; Edlund, Håkan; Hedenström, Erik; Lindblom, Göran

    2004-02-17

    The temperature-versus-composition phase diagrams of eight different 1-alkylpyridinium octane-1-sulfonates (APOSs) in water were studied by 1H NMR, 2H NMR, pulsed gradient spin-echo NMR, small-angle X-ray diffraction, differential scanning calorimetry, surface tension and conductivity measurements, and polarizing microscopy. The number of carbons (n(c)) in the hydrocarbon chain of the pyridinium counterions was varied from n(c) = 1 to n(c) = 8 to study how the phase behavior of the APOS/2H2O systems was affected by a change in the chain length of the counterion. The sodium octane-1-sulfonate (NaOS)/water system was used as a reference. This system formed an isotropic micellar solution (L1) phase and a normal hexagonal (H(I)) phase. All APOSs were readily soluble in water and formed L1 phases. The surface tension above the critical micelle concentration for n(c) between 1 and 3 was higher than that for NaOS, and it decreased steadily for the different APOSs with increasing chain length. The area per molecule at the air/solution interfaces was rather constant at 68 A2 for n(c) between 1 and 7. For 1-octylpyridinium octane-1-sulfonate (OPOS), it was about 5 A2 smaller, which was just outside the estimated error. However, the smallest area was obtained for NaOS. At higher surfactant concentrations, liquid crystalline phases formed. Both cubic and H(I) phases were found for n(c) = 1 and 2, while for n(c) between 3 and 5 only an H(I) phase was observed. H(I) and lamellar liquid crystalline (Lalpha) phases formed for n(c) = 6 and 7. The only liquid crystalline phase found in the OPOS system was a Lalpha phase. The NaOS H(I) phase was the only liquid crystalline phase that showed a linear relation between the 2H2O NMR quadrupolar splitting (deltaW) and Xsurf/X(W), where Xsurf and X(W) are the mole fractions of surfactant and water. The OPOS lamellae were found to be much thinner than expected, indicating a defect lamellar structure. This was further supported by the

  6. Diffusion Coefficient of Tin(II) Methanesulfonate in Ionic Liquid and Methane Sulfonic Acid (MSA) Solvent

    NASA Astrophysics Data System (ADS)

    Yang, Kok Kee; Mahmoudian, M. R.; Ebadi, Mehdi; Koay, Hun Lee; Basirun, Wan Jeffrey

    2011-12-01

    Voltammetry and chronoamperometry for the electrodeposition of tin from Tin(II) methane sulfonate mixed with ionic liquid and methane sulfonate acid at room temperature was studied. Cyclic voltammetry shows redox waves of Tin(II), which proves that the electrodeposition of tin from Tin(II) methane sulfonate is a diffusion-controlled process. The diffusion coefficient of Tin(II) ions in the solvent mixture showed good agreement from both voltammetry and chronoamperometry results. The diffusion coefficient of Tin(II) in the mixture was much smaller than in aqueous solution, and it depends on the anion of the ionic liquid.

  7. Raman and Luminescent Spectra of Sulfonated Zn Phthalocyanine Enhanced by Gold Nanoparticles

    NASA Astrophysics Data System (ADS)

    Kavelin, V.; Fesenko, O.; Dubyna, H.; Vidal, C.; Klar, T. A.; Hrelescu, C.; Dolgov, L.

    2017-03-01

    Sulfonated Zn phthalocyanine, as a prospective photosensitizer in the photodynamic therapy of tumors, is investigated by means of Raman, infrared, and fluorescence spectroscopies. Conventional and surface-enhanced spectra from this photosensitizer are obtained and compared. Gold nano-islands attached to silica cores (Au-SiO2) are proposed as nanostructures providing plasmonically enhanced signals. Pronounced enhancement of Raman and infrared spectral bands from sulfonated Zn phthalocyanine allows their more convenient assignment with vibrational modes of sulfonated Zn phthalocyanine. In comparison to Raman and IR, the fluorescence is less enhanced by Au-SiO2 particles.

  8. Studies on the induction of permeability in Ascaris lumbricoides eggs.

    PubMed

    Barrett, J

    1976-08-01

    The initial process in the hatching mechanism of Ascaris eggs is the sudden onset of permeability in the previously impermeable ascaroside membrane. During this change the ascaroside membrane remains intact and no chemical changes can be detected. Using the molecular probe 1-anilino-8-naphthalene sulphonic acid no conformational changes were detected in the ascaroside membrane during the induction of permeability. It is suggested that either the permeability change is due to a very localized chemical or conformational change, not detectable by conventional analytical techniques, or the change is due to mechanical damage of the ascaroside membrane, brought about by the activity of the infective larva.

  9. Siladenoserinols A-L: new sulfonated serinol derivatives from a tunicate as inhibitors of p53-Hdm2 interaction.

    PubMed

    Nakamura, Yuichi; Kato, Hikaru; Nishikawa, Tadateru; Iwasaki, Noriyuki; Suwa, Yoshiaki; Rotinsulu, Henki; Losung, Fije; Maarisit, Wilmar; Mangindaan, Remy E P; Morioka, Hiroshi; Yokosawa, Hideyoshi; Tsukamoto, Sachiko

    2013-01-18

    Siladenoserinols A-L were isolated from a tunicate as inhibitors of p53-Hdm2 interaction, a promising target for cancer chemotherapy. Their structures including the absolute configurations were elucidated to be new sulfonated serinol derivatives, each of which contains a 6,8-dioxabicyclo[3.2.1]octane unit and either glycerophosphocholine or glycerophosphoethanolamine moiety. They inhibited p53-Hdm2 interaction with IC(50) values of 2.0-55 μM. Among them, siladenoserinol A and B exhibited the strongest inhibition with an IC(50) value of 2.0 μM.

  10. Chemiluminescence detection with water-soluble iridium(III) complexes containing a sulfonate-functionalised ancillary ligand.

    PubMed

    Truong, Josephine; Spilstead, Kara B; Barbante, Gregory J; Doeven, Egan H; Wilson, David J D; Barnett, Neil W; Henderson, Luke C; Altimari, Jarrad M; Hockey, Samantha C; Zhou, Ming; Francis, Paul S

    2014-11-21

    The chemiluminescence from four cyclometalated iridium(III) complexes containing an ancillary bathophenanthroline-disulfonate ligand exhibited a wide range of emission colours (green to red), and in some cases intensities that are far greater than the commonly employed benchmark reagent, [Ru(bpy)3](2+). A similar complex incorporating a sulfonated triazolylpyridine-based ligand enabled the emission to be shifted into the blue region of the spectrum, but the responses with this complex were relatively poor. DFT calculations of electronic structure and emission spectra support the experimental findings.

  11. Synthesis and characterizations of electrospun sulfonated poly (ether ether ketone) SPEEK nanofiber membrane

    NASA Astrophysics Data System (ADS)

    Hasbullah, N.; Sekak, K. A.; Ibrahim, I.

    2016-07-01

    A novel electrospun polymer electrolyte membrane (PEM) based on Sulfonated Poly (ether ether ketone) were prepared and characterized. The poly (ether ether ketone) PEEK was sulfonated using concentrated sulfuric acid at room temperature for 60 hours reaction time. The degree sulfonation (DS) of the SPEEK are 58% was determined by H1 NMR using area under the peak of the hydrogen shielding at aromatic ring of the SPEEK. Then, the functional group of the SPEEK was determined using Fourier transfer infrared (FTIR) showed O-H vibration at 3433 cm-1 of the sulfonated group (SO2-OH). The effect of the solvent and polymer concentration toward the electrospinning process was investigated which, the DMAc has electrospun ability compared to the DMSO. While, at 20 wt.% of the polymer concentration able to form a fine and uniform nanofiber, this was confirmed by FESEM that shown electrospun fiber mat SPEEK surface at nano scale diameter.

  12. A Modular Synthetic Approach to Isosteric Sulfonic Acid Analogues of the Anticoagulant Pentasaccharide Idraparinux.

    PubMed

    Mező, Erika; Eszenyi, Dániel; Varga, Eszter; Herczeg, Mihály; Borbás, Anikó

    2016-11-11

    Heparin-based anticoagulants are drugs of choice in the therapy and prophylaxis of thromboembolic diseases. Idraparinux is a synthetic anticoagulant pentasaccharide based on the heparin antithrombin-binding domain. In the frame of our ongoing research aimed at the synthesis of sulfonic acid-containing heparinoid anticoagulants, we elaborated a modular pathway to obtain a series of idraparinux-analogue pentasaccharides bearing one or two primary sulfonic acid moieties. Five protected pentasaccharides with different C-sulfonation patterns were prepared by two subsequent glycosylation reactions, respectively, using two monosaccharide and four disaccharide building blocks. Transformation of the protected derivatives into the fully O-sulfated, O-methylated sulfonic acid end-products was also studied.

  13. Titania-based molecularly imprinted polymer for sulfonic acid dyes prepared by sol-gel method.

    PubMed

    Li, Man; Li, Rong; Tan, Jin; Jiang, Zi-Tao

    2013-03-30

    A novel titania-based molecularly imprinted polymer (MIP) was synthesized through sol-gel process with sunset yellow (Sun) as template, without use of functional monomer. MIP was used as a solid-phase extraction material for the isolation and enrichment of sulfonic acid dyes in beverages. The results showed that MIP exhibited better selectivity, higher recovery and adsorption capacity for the sulfonic acid dyes compared to the non-imprinted polymer (NIP). MIP presented highest extraction selectivity to Sun when pH less than or equal to 3. The adsorption capacity was 485.9 mg g(-1), which was larger than that of NIP (384.7 mg g(-1)). The better clean-up ability demonstrated the capability of MIP for the isolation and enrichment of sulfonic acid dyes in complicated food samples. The mean recoveries for the sulfonic acid dyes on MIP were from 81.9% to 97.2% in spiked soft drink.

  14. REVISITING NUCLEOPHILIC SUBSTITUTION REACTIONS: MICROWAVE-ASSISTED SYNTHESIS OF AZIDES, THIOCYANATES AND SULFONES IN AQUEOUS MEDIUM

    EPA Science Inventory

    A practical, rapid and efficient microwave (MW) promoted synthesis of various azides, thiocyanates and sulfones, is described in aqueous medium. This general and expeditious MW-enhanced nucleophilic substitution approach uses easily accessible starting materials such as halides o...

  15. EFFECTS OF PRENATAL PERFLUOROOCTANE SULFONATE (PFOS) EXPOSURE ON LUNG MATURATION IN THE PERINATAL RAT

    EPA Science Inventory

    Background: Perfluorooctane sulfonate (PFOS), found widely in wildlife and humans, is environmentally and metabolically stable. Environmental PFOS may be from its use as a surfactant, hydrolysis of perfluorooctanesulfonyl fluoride, and degradation of N-alkyl-perfluorooctanesulfon...

  16. Magnetite-supported sulfonic acid: a retrievable nanocatalyst for the Ritter reaction and multicomponent reactions

    EPA Science Inventory

    Magnetite-sulfonic acid (NanocatFe-OSO3H), prepared by wet-impregnation method, serves as a magnetically retrievable sustainable catalyst for the Ritter reaction which can be used in several reaction cycles without any loss of activity.

  17. Utilization of common ditch vegetation in the reduction of fipronil and its sulfone metabolite

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fipronil, a phenylpyrazole insecticide and its oxidative sulfone metabolite are two potential nonpoint source pollutants from treated rice and cotton production. A consequence of these pollutants occurring in surface runoff is degradation of downstream aquatic ecosystems. Utilization of primary inte...

  18. Synthesis of sulfonated oxindoles by potassium iodide catalyzed arylsulfonylation of activated alkenes with sulfonylhydrazides in water.

    PubMed

    Li, Xiaoqing; Xu, Xiangsheng; Hu, Peizhu; Xiao, Xuqiong; Zhou, Can

    2013-07-19

    A catalytic system consisting of KI, 18-crown-6, and TBHP for arylsulfonylation of activated alkenes with sulfonylhydrazides as sulfonyl precursor is described. This protocol provides a practical and environmentally benign method for the construction of sulfonated oxindoles in water.

  19. Anhydrous state proton and lithium ion conducting solid polymer electrolytes based on sulfonated bisphenol-A-poly(arylene ethers)

    NASA Astrophysics Data System (ADS)

    Guha Thakurta, Soma

    Sulfonated polymer based solid polymer electrolytes (SPEs) have received considerable interest in recent years because of their wide variety of applications particularly in fuel cells, batteries, supercapacitors, and electrochromic devices. The present research was focused on three interrelated subtopics. First, two different bisphenol-A-poly(arylene ethers), polyetherimide (PEI) and polysulfone (PSU) were sulfonated by a post sulfonation method to various degrees of sulfonation, and their thermal and mechanical properties were examined. The effects of poly(arylene ether) chemical structure, reaction time, concentration, and types of sulfonating agents on sulfonation reaction were investigated. It was found that deactivation of bisphenol A unit caused by the electron withdrawing imide, retarded the sulfonation of PEI compared to PSU. Sulfonation conducted with a high concentration of sulfonating agent and/or prolonged reaction time exhibited evidence of degradation at the isopropylidene unit. The degradation occurred through the same mechanistic pathway with the two different sulfonating agents, chlorosulfonic acid (CSA) and trimethylsilyl chlorosulfonate (TMSCS). The degradation was faster with CSA than its silyl ester, TMSCS, and was evident even at low acid concentration. Second, novel anhydrous proton conducting solid polymer electrolytes (SPEs) were prepared by the incorporation of 1H-1,2,4-triazole (Taz) as a proton solvent in sulfonated polyetherimide (SPEI) matrix. The size, shape, and state of dispersion (crystal morphology) of triazole crystals in SPEI were examined as a function of degree of sulfonation and triazole concentration. Increasing sulfonic acid content caused reduction of triazole crystallite size, hence the depression of melting temperature and their uniform distribution throughout the sulfonated polymer matrix. The increased rate of structure diffusion within the smaller size crystals due to the improved molecular mobility contributed

  20. Morphological Behavior of Sulfonated Styrene-Ethylene/Propylene-Styrene Triblock Copolymers

    DTIC Science & Technology

    2006-02-01

    ionomers possessing short (1K g/mol) styrene blocks and various rubber block lengths were synthesized via sequential anionic polymerization of styrene...isoprene, and styrene followed by hydrogenation and sulfonation. The ionomers were then characterized by small-angle x-ray scattering (SAXS) and atomic...spherical. 15. SUBJECT TERMS block copolymer, SAXS, ionomer , sulfonated polystyrene, SEPS 16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE

  1. Phase segregation of sulfonate groups in Nafion interface lamellae, quantified via neutron reflectometry fitting techniques for multi-layered structures.

    PubMed

    DeCaluwe, Steven C; Kienzle, Paul A; Bhargava, Pavan; Baker, Andrew M; Dura, Joseph A

    2014-08-21

    Neutron reflectometry analysis methods for under-determined, multi-layered structures are developed and used to determine the composition depth profile in cases where the structure is not known a priori. These methods, including statistical methods, sophisticated fitting routines, and coupling multiple data sets, are applied to hydrated and dehydrated Nafion nano-scaled films with thicknesses comparable to those found coating electrode particles in fuel cell catalyst layers. These results confirm the lamellar structure previously observed on hydrophilic substrates, and demonstrate that for hydrated films they can accurately be described as layers rich in both water and sulfonate groups alternating with water-poor layers containing an excess of fluorocarbon groups. The thickness of these layers increases slightly and the amplitude of the water volume fraction oscillation exponentially decreases away from the hydrophilic interface. For dehydrated films, the composition oscillations die out more rapidly. The Nafion-SiO2 substrate interface contains a partial monolayer of sulfonate groups bonded to the substrate and a large excess of water compared to that expected by the water-to-sulfonate ratio, λ, observed throughout the rest of the film. Films that were made thin enough to truncate this lamellar region showed a depth profile nearly identical to thicker films, indicating that there are no confinement or surface effects altering the structure. Comparing the SLD profile measured for films dried at 60 °C to modeled composition profiles derived by removing water from the hydrated lamellae suggests incomplete re-mixing of the polymer groups upon dehydration, indicated limited polymer mobility in these Nafion thin films.

  2. Viscoelastic Behavior of Low Molecular Weight Sulfonated Polystyrene Ionomers

    NASA Astrophysics Data System (ADS)

    Zhao, Hongying

    Ionomers are those hydrophobic polymers having small amounts of bonded ionic groups. The introduction of the ionic groups into polymer chain produces large changes in the physical, mechanical and rheological properties of the parent polymer. Characterization of the effect of the ionic interactions on the rheology is complicated by the difficulty in separating effects due to molecular entanglements and the ionic interactions. In this study, low molecular weight (Mw=4000) sulfonated polystyrene (SPS) was used to study the dynamic and steady shear rheology of SPS ionomers. The polymer chain length used was far below the entanglement molecular weight of polystyrene and effects of molecular entanglements will be absent. Any polymer chain entanglements or lengthening behavior on the melt rheology should be due to the ionic interactions. Random SPS ionomers with two sulfonation levels were examined, 2.5 and 4.8 mol%, which corresponded, respectively, to one and two sulfonate groups per chain on average. The metal counterions was varied across the alkali metal series of the periodic table. Morphology of the ionomer was characterized by using small angle x-ray scattering (SAXS) analysis, and dynamic and steady shear measurements were performed to investigate rheological behavior of the ionomers. Glass transition temperatures of the ionomers increased with increasing ion concentration but were insensitive to cation used. The scattering peak in SAXS indicates the existence of the nanophase separated ionic clusters. The strong ionic nanophase persist up to very high temperatures and is not sensitive to the external stress. Time-temperature superposition (TTS) of G' worked reasonably well while TTS of G" failed for most ionomers. Ionic interactions increased the terminal relaxation time of the melts as much as seven orders of magnitude greater than the unentangled PS melt. The zero shear viscosity and first normal stress coefficients scaled with cq/a, where c was the

  3. Vibrational spectroscopic study of pure and silica-doped sulfonated poly(ether ether ketone) membranes

    NASA Astrophysics Data System (ADS)

    Rangasamy, Vijay Shankar; Thayumanasundaram, Savitha; Seo, Jin Won; Locquet, Jean-Pierre

    2015-03-01

    We report the vibrational properties of sulfonated poly(ether ether ketone) (SPEEK) membranes, used as electrolytes in proton exchange membrane (PEM) fuel cells, studied by Fourier transform infrared (FTIR) spectroscopy. We discuss the changes in the vibrational modes of the functional groups present in the polymer arising due to the sulfonation process and the subsequent incorporation of silica particles functionalized with sulfonic acid group. From the infrared spectra, we confirm the incorporation of sulfonic acid group in the polymer chain as well as in the functionalized silica particles. We have also measured the variations in the peak area ratio of the characteristic out-of-plane vibrations of the aromatic rings in the PEEK polymer at 1280 cm-1 with respect to a reference peak at 1305 cm-1. These values were correlated to the crystallinity (XC) values experimentally determined by DSC technique, providing a non-destructive means to calculate the crystallinity of polymer membranes. The calculated XC values were in good agreement with the experimental values. The crystallinity was observed to decrease with increasing degree of sulfonation (DS), indicating the crystalline-to-amorphous phase modification of the polymer by sulfonation, which along with the enhanced ion-exchange capacity and water uptake, is responsible for the improved ionic conductivity at higher DS values.

  4. Polymer electrolytes based on sulfonated polysulfone for direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Lufrano, F.; Baglio, V.; Staiti, P.; Arico', A. S.; Antonucci, V.

    This paper reports the development and characterization of sulfonated polysulfone (SPSf) polymer electrolytes for direct methanol fuel cells. The synthesis of sulfonated polysulfone was performed by a post sulfonation method using trimethyl silyl chlorosulfonate as a mild sulfonating agent. Bare polysulfone membranes were prepared with two different sulfonation levels (60%, SPSf-60 and 70%, SPSf-70), whereas, a composite membrane of SPSf-60 was prepared with 5 wt% silica filler. These membranes were investigated in direct methanol fuel cells (DMFCs) operating at low (30-40 °C) and high temperatures (100-120 °C). DMFC power densities were about 140 mW cm -2 at 100 °C with the bare SPSf-60 membrane and 180 mW cm -2 at 120 °C with the SPSf-60-SiO2 composite membrane. The best performance achieved at ambient temperature using a membrane with high degree of sulfonation (70%, SPSf-70) was 20 mW cm -2 at atmospheric pressure. This makes the polysulfone-based DMFC suitable for application in portable devices.

  5. Synthesis of analogs of juvenile hormone on the basis of the telomerization reaction of piperylene with sulfones

    SciTech Connect

    Tolstikov, G.A.; Rozentsvet, O.A.; Pantukh, B.I.; Khalilov, L.M.

    1986-10-20

    In continuing the work on the study of the telomerization of 1,3-dienes with sulfones containing an active H atom, and also with the aim of synthesizing analogs of juvenile hormone (JH) based on the telomers obtained, they studied the catalytic telomerization of 1,3-pentadiene (piperylene) with ..beta..-substituted sulfonates. It was established that trans-piperlyene participates in the telomerization reaction with sulfones in the presence of the catalytic system PdCl/sub 2/(Ph/sub 3/P)/sub 2/-PhONa. Methyl 2-phenylsulfonyl-3,7-dimethyl-4(E), 9-decadienecarboxylate (II) is formed in a yield of 65% by the reaction of methyl phenylsulfonylacetate (I) with piperylene in the course of 20 h at 85/sup 0/C. The presence of absorption bands at 920 (CH/sub 2/=C) and 980 cm/sup -1/ (E-CH=CH) in the IR spectrum of compound (II) and the presence of a group of multiplet signals at delta 4.8-5.3 ppm in the PMR spectrum, corresponding to five protons of double bonds, indicate the addition of two molecules of piperylene to the molecule of the sulfone (I). The oxidation with oxygen on a Pd/Cu-catalyst proceeds smoothly to the methyl ketone (III); this clearly confirms the presence of the terminal C=C bond in the telomer (II). In the PMR spectrum of (II), notice is taken of the group of signals in the region of 3.30-3.53 ppm corresponding to three methoxy protons. There are three pairs of doublets (J = 7 Hz) in the region of 0.1-1.3 ppm which correspond to the methyl group. The complexity of the PMR spectrum is probably explained by the fact that the reaction leads to the formation of a complex mixture of diastereoisomers. As was to be expected, methyl 3,7-dimethyl-4,9-decadienoate (IV) is formed as the sole product with a yield of 70% in the desulfonation of the telomer (II) using Na/Hg in methanol according to the method of (5); the structure of (IV) was established with the aid of /sup 13/C NMR spectroscopy.

  6. Sulfonated nanocellulose for the efficient dispersive micro solid-phase extraction and determination of silver nanoparticles in food products.

    PubMed

    Ruiz-Palomero, Celia; Soriano, M Laura; Valcárcel, Miguel

    2016-01-08

    This paper reports a simple approach to Analytical Nanoscience and Nanotechnology (AN&N) that integrates the nanotool, sulfonated nanocellulose (s-NC), and nanoanalyte, silver nanoparticles (AgNPs), in the same analytical process by using an efficient, environmentally friendly dispersive micro solid-phase extraction (D-μSPE) capillary electrophoresis (CE) method with s-NC as sorbent material. Introducing negatively charged sulfate groups onto the surface of cellulose enhances its surface chemistry and enables the extraction and preconcentration of AgNPs of variable diameter (10, 20 and 60nm) and shell composition (citrate and polyvinylpyrrolidone coatings) from complex matrices into a cationic surfactant. In this way, AgNPs of diverse nature were successfully extracted onto the s-NC sorbent and then desorbed into an aqueous solution containing thiotic acid (TA) prior to CE without the need for any labor-intensive cleanup. The ensuing eco-friendly D-μSPE method exhibited a linear response to AgNPs with a limit of detection (LOD) of 20μg/L. Its ability to specifically recognize AgNPs of different sizes was checked in orange juice and mussels, which afforded recoveries of 70.9-108.4%. The repeatability of the method at the limit of quantitation (LOQ) level was 5.6%. Based on the results, sulfonated nanocellulose provides an efficient, cost-effective analytical nanotool for the extraction of AgNPs from food products.

  7. Crystal structure of di­ethyl­ammonium aniline-4-sulfonate anilinium-4-sulfonate

    PubMed Central

    Toure, Assane; Diop, Libasse; Diop, Cheikh Abdoul Khadir; Oliver, Allen G.

    2016-01-01

    The title compound, C4H12N+·C6H6NO3S−·C6H7NO3S, consists of an ion pair and a zwitterionic neutral mol­ecule. The cation adopts an extended conformation [C—C—N—C torsion angles = 177.1 (3) and −178.4 (3)°]. In the crystal, the components are linked by N—H⋯O and N—H⋯N hydrogen bonds, generating a three-dimensional network, which is consolidated by weak C—H⋯O inter­actions. PMID:27980842

  8. Perfluoroctane sulfonate-induced changes in fetal rat liver ...

    EPA Pesticide Factsheets

    In utero exposure of rats to perfluorooctane sulfonate (PFOS, C8F17SO3), a widely disseminated product of the surfactant and coating industries, is associated with residual hepatoxic complications in the surviving offspring. This hepatocellular hypertrophy resembles that observed in adults and is characterized by peroxisome proliferation, lower serum cholesterol and fatty acid concentrations, and hypothyroxemia, most of which are suspected to be manifested through PPARalpha-mediated transcriptional regulation. The purpose of the present investigation was to develop a comprehensive characterization of the transcriptional changes associated with prenatal exposure to PFOS using global gene expression array analyses. Gravid Sprague-Dawley rats were administered 3 mg/kg PFOS by gavage daily from gestational day 2-20 and terminated on day 21. Although there was no treatment-related teratology, there was a substantial effect of PFOS on the perinatal hepatic transcriptome – 225 unique transcripts were identified as statistically increased and 220 decreased by PFOS exposure; few transcripts were changed by more than two-fold. Although the Ppara transcript itself was not affected, there was a significant increase in expression of gene transcripts associated with hepatic peroxisomal proliferation as well as those responsible for fatty acid activation, transport and oxidation (both mitochondrial and peoxisomal) pathways. Additional metabolic pathways altered by in ut

  9. Micellization behavior of aromatic moiety bearing hybrid fluorocarbon sulfonate surfactants.

    PubMed

    Wadekar, Mohan N; Boekhoven, Job; Jager, Wolter F; Koper, Ger J M; Picken, Stephen J

    2012-02-21

    Aggregation behavior and thermodynamic properties of two novel homologous aromatic moiety bearing hybrid fluorocarbon surfactants, sodium 2-(2-(4-ethylphenyl)-1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate (1) and sodium 2-(1,1,2,2-tetrafluoro-2-(4-vinylphenyl)ethoxy)-1,1,2,2-tetrafluoroethanesulfonate (2) were studied using surface tension measurements and isothermal titration calorimetry (ITC) in dilute aqueous solutions at room temperature. Because of the aromatic group in the hydrophobic tail, both surfactants are soluble at room temperature unlike their starting precursor, 5-iodooctafluoro-3-oxapentanesulfonate as well as several other fluorocarbon sulfonic acid salts. Moreover, the surfactant 2 has the ability that it can be polymerized once microemulsions are formed with it. The ionic conductivity measurements of 1 at five different temperatures from 288 to 313 K were carried out to study the effect of temperature on the micellization and its thermodynamics. The pseudophase separation model was applied to estimate thermodynamic quantities from conductivity data. The Gibbs energy of micellization versus temperature exhibited the characteristic U-shaped behavior with a minimum at 306 K. The micellization process was found to be largely entropy driven. Because of its hybrid structure, the entropy change of micellization for 1 was larger than what is common for hydrocarbon surfactants like SDS but less than for fully fluorinated surfactants like NaPFO. The micellization process was found to be following the entropy-enthalpy compensation phenomena.

  10. Tissue Distribution Of Chloroaluminium Sulfonated Phthalocyanine In Dogs

    NASA Astrophysics Data System (ADS)

    M. M.; H. C.; Newman

    1989-06-01

    Chloroaluminum sulfonated phthalocyanine (A1PCS) was administered intravenously to clinically normal dogs, and A1PCS levels were determined in tissues using a sensitive assay. A1PCS accumulated to high levels in liver, spleen, bone marrow, kidney, and lung. These tissue levels confirm previous determinations in mice and rats. Only a small amount of dye was retained in skin and very small amounts in muscle and brain. A1PCS was cleared from the blood within 24 h, and excreted primarily by urine. Serum clearance was faster in males than in females. There were also significant tissue distribution differences between the genders, particularly during the first 12 h. The low levels of A1PCS in skin suggest that cutaneous photosensitivity and toxic skin reactions using this photosensitizer in photodynamic therapy of cancer may be eliminated. The difference in tissue distribution between genders is not only intriguing, but indicates that the optimal time window for treatment of various tissue sites may vary by gender.

  11. Thermoanalytical investigation of some sulfone-containing drugs.

    PubMed

    Salama, Nahla N; El Ries, Mohammed A; Toubar, Safaa; Abd El Hamid, Maha; Walash, Mohammed I

    2012-01-01

    The thermal behavior of some sulfone-containing drugs, namely, dapsone (DDS), dimethylsulfone (MSM), and topiramate (TOP) in drug substances, and products were investigated using different thermal techniques. These include thermogravimetry (TGA), derivative thermogravimetry (DTG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC). The thermogravimetric data allowed the determination of the kinetic parameters: activation energy (E(a)), frequency factor (A), and reaction order (n). The thermal degradation of dapsone and topiramate was followed a first-order kinetic behavior. The calculated data evidenced a zero-order kinetic for dimethylsulfone. The relative thermal stabilities of the studied drugs have been evaluated and follow the order DDS > TOP > MSM. The purity was determined using DSC for the studied compounds, in drug substances and products. The results were in agreement with the recommended pharmacopoeia and manufacturer methods. DSC curves obtained from the tablets suggest compatibility between the drugs, excipients and/or coformulated drugs. The fragmentation pathway of dapsone with mass spectrometry was taken as example, to correlate the thermal decomposition with the resulted MS-EI. The decomposition modes were investigated, and the possible fragmentation pathways were suggested by mass spectrometry.

  12. Thermoanalytical Investigation of Some Sulfone-Containing Drugs

    PubMed Central

    Salama, Nahla N.; El Ries, Mohammed A.; Toubar, Safaa; Abd El Hamid, Maha; Walash, Mohammed I.

    2012-01-01

    The thermal behavior of some sulfone-containing drugs, namely, dapsone (DDS), dimethylsulfone (MSM), and topiramate (TOP) in drug substances, and products were investigated using different thermal techniques. These include thermogravimetry (TGA), derivative thermogravimetry (DTG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC). The thermogravimetric data allowed the determination of the kinetic parameters: activation energy (E a), frequency factor (A), and reaction order (n). The thermal degradation of dapsone and topiramate was followed a first-order kinetic behavior. The calculated data evidenced a zero-order kinetic for dimethylsulfone. The relative thermal stabilities of the studied drugs have been evaluated and follow the order DDS > TOP > MSM. The purity was determined using DSC for the studied compounds, in drug substances and products. The results were in agreement with the recommended pharmacopoeia and manufacturer methods. DSC curves obtained from the tablets suggest compatibility between the drugs, excipients and/or coformulated drugs. The fragmentation pathway of dapsone with mass spectrometry was taken as example, to correlate the thermal decomposition with the resulted MS-EI. The decomposition modes were investigated, and the possible fragmentation pathways were suggested by mass spectrometry. PMID:22792516

  13. Phthalocyanines And Their Sulfonated Derivatives As Photosensitizers In Photodynamic Therapy.

    NASA Astrophysics Data System (ADS)

    Riesz, Peter; Krishna, C. Murali

    1988-02-01

    Photodynamic therapy (PDT) of human tumors with hematoporphyrin derivative (HpD) has achieved encouraging results. However, HpD is a complex mixture whose composition varies in different preparations and with time of storage. The future promise of PDT for cancer treatment depends on the development of new chemically defined sensitizers which absorb more strongly than HpD in the 600-800 nm region. A shift to higher wavelengths is desirable since it allows increased light penetration in human tissues. In vivo, these sensitizers should be non-toxic, localize selectively in tumors and generate cytotoxic species upon illumination with a high quantum yield. These damaging species may be singlet oxygen (1O2) produced by the transfer of energy from the triplet state of the sensitizer to oxygen (Type II) or superoxide anion radicals formed by electron transfer to oxygen or substrate radicals generated by electron or hydrogen transfer directly from the sensitizer (Type I). The recent work of several groups indicating that phthalocyanines and their water soluble derivatives are promising candidates for PDT is reviewed. The photophysics, photochemistry, photosensitized killing of cultured mammalian cells and the use for in vivo photodynamic therapy of phthalocyanines is outlined. Our studies of the post-illumination photohemolysis of human red blood cells as a model system for membrane photomodification sensitized by phthalocyanine sulfonates are consistent with the predominant role of 1O2 as the damaging species.

  14. Determination of perfluoroalkyl carboxylic, sulfonic, and phosphonic acids in food.

    PubMed

    Ullah, Shahid; Alsberg, Tomas; Vestergren, Robin; Berger, Urs

    2012-11-01

    A sensitive and accurate method was developed and validated for simultaneous analysis of perfluoroalkyl carboxylic acids, sulfonic acids, and phosphonic acids (PFPAs) at low picograms per gram concentrations in a variety of food matrices. The method employed extraction with acetonitrile/water and cleanup on a mixed-mode co-polymeric sorbent (C8 + quaternary amine) using solid-phase extraction. High-performance liquid chromatographic separation was achieved on a C18 column using a mobile phase gradient containing 5 mM 1-methyl piperidine for optimal chromatographic resolution of PFPAs. A quadrupole time-of-flight high-resolution mass spectrometer operating in negative ion mode was used as detector. Method detection limits were in the range of 0.002 to 0.02 ng g(-1) for all analytes. Sample preparation (extraction and cleanup) recoveries at a spiking level of 0.1 ng g(-1) to a baby food composite were in the range of 59 to 98 %. A strong matrix effect was observed in the analysis of PFPAs in food extracts, which was tentatively assigned to sorption of PFPAs to the injection vial in the solvent-based calibration standard. The method was successfully applied to a range of different food matrices including duplicate diet samples, vegetables, meat, and fish samples.

  15. Fate of linear alkylbenzene sulfonate in the Mississippi River

    USGS Publications Warehouse

    Tabor, C.F.; Barber, L.B.

    1996-01-01

    The 2 800-km reach of the Mississippi River between Minneapolis, MN, and New Orleans, LA, was examined for the occurrence and fate of linear alkylbenzene sulfonate (LAS), a common anionic surfactant found in municipal sewage effluents. River water and bottom sediment were sampled in the summer and fall of 1991 and in the spring of 1992. LAS was analyzed using solid- phase extraction/derivatization/gas chromatography/mass spectrometry. LAS was present on all bottom sediments at concentrations ranging from 0.01 to 20 mg/kg and was identified in 21% of the water samples at concentrations ranging from 0.1 to 28.2 ??g/L. The results indicate that LAS is a ubiquitous contaminant on Mississippi River bottom sediments and that dissolved LAS is present mainly downstream from the sewage outfalls of major cities. The removal of the higher LAS homologs and external isomers indicates that sorption and biodegradation are the principal processes affecting dissolved LAS. Sorbed LAS appears to degrade slowly.

  16. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) contamination from textiles.

    PubMed

    Supreeyasunthorn, Phenpimuk; Boontanon, Suwanna K; Boontanon, Narin

    2016-01-01

    The goals of this study were to determine the concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in textiles and to determine PFOS and PFOA contamination in textile washing water. Quantification analysis was performed by high performance liquid chromatography coupled with tandem mass spectrometry. Analysis of 32 textile samples by methanol extraction revealed that the average concentrations of PFOS and PFOA were 0.18 µg m(-2) (0.02 to 0.61 µg m(-2)) and 2.74 µg m(-2) (0.31 to 14.14 µg m(-2)), respectively. Although the average concentration of PFOS found in textile samples was below European Union (EU) Commission regulations (<1 µg m(-2)), the average concentration of PFOA was 2.74 µg m(-2), and 68.75% of textile samples had PFOA concentrations exceeding 1 µg m(-2). Thus, based on these results, the concentration of PFOA in products should also be regulated. Experiments on PFOS and PFOA leaching into washing water were conducted. The maximum concentrations of PFOS and PFOA were measured after the first washing; the concentrations gradually decreased with each subsequent washing. PFOS and PFOA migrated from textiles and were released into the environment, with disappearance percentages of 29.8% for PFOS and 99% for PFOA. The data presented in this study showed that textiles could be a significant direct and indirect source of PFOS and PFOA exposure for both humans and the environment.

  17. Recycle waste salt as reagent: a one-pot substitution/Krapcho reaction sequence to α-fluorinated esters and sulfones.

    PubMed

    Zhu, Feng; Xu, Peng-Wei; Zhou, Feng; Wang, Cui-Hong; Zhou, Jian

    2015-02-20

    A "one-pot" tandem substitution/Krapcho reaction is reported for the facile synthesis of α-fluorinated esters and sulfones, which utilizes the byproduct salt formed in the substitution step as an indispensible reagent to facilitate the Krapcho reaction step. This represents the first sustainable tandem reaction that internally recycles the waste salt formed in the upstream step as the reagent for the downstream step.

  18. Design of a highly efficient and water-tolerant sulfonic acid nanoreactor based on tunable ordered porous silica for the von Pechmann reaction.

    PubMed

    Karimi, Babak; Zareyee, Daryoush

    2008-09-18

    Among a number of different sulfonic acid nanoreactors prepared, 5 having both acidic sites and phenyl groups located inside the mesochannels of SBA-15 was shown to be the most active and reusable catalyst in the von Pechmann reaction. The mesochannels, and covalently anchored organic groups, provide a synergistic means of an efficient approach of the reactants to acidic sites, enough space for the subsequent cyclization, and suitable hydrophobicity to drive out the water byproduct.

  19. Shifting from hydrogen bond network to π-π stacking: a key mechanism for reversible thermochromic sulfonated poly(ether ether ketone).

    PubMed

    Jarumaneeroj, Chatchai; Tashiro, Kohji; Chirachanchai, Suwabun

    2014-08-01

    Sulfonated poly(ether ether ketone) (SPEEK) thin film performs reversible thermochromic property by developing the color to be yellowish at the temperature above 190 °C. The detailed analyses based on temperature-dependent techniques suggest the thermal treatment inducing the shifting of the hydrogen bond network between the sulfonated group and the hydrated water molecules to the π-π stacking among aromatic rings in SPEEK chains. Although it is general that the polymer chain packing is unfavorable at high temperature, the present work shows a good example that when the polymer chains can form specific molecular interaction, such as π-π stacking, even in harsh thermal treatment, a rearrangement will effectively occur, which leads to an external stimuli-responsive property.

  20. Imidazolium Sulfonates as Environmental-Friendly Catalytic Systems for the Synthesis of Biologically Active 2-Amino-4H-chromenes: Mechanistic Insights.

    PubMed

    Velasco, Jacinto; Pérez-Mayoral, Elena; Calvino-Casilda, Vanesa; López-Peinado, Antonio J; Bañares, Miguel A; Soriano, Elena

    2015-09-10

    Ionic Liquids (ILs) are valuable reaction media extremely useful in industrial sustainable organic synthesis. We describe here the study on the multicomponent reaction (MCR) between salicylaldehyde (2) and ethyl cyanoacetate (3), catalyzed by imidazolium sulfonates, to form chromenes 1, a class of heterocyclic scaffolds exhibiting relevant biological activity. We have clarified the reaction mechanism by combining the experimental results with computational studies. The results reported herein suggest that both the imidazolium core and the sulfonate anions in the selected ILs are involved in the reaction course acting as hydrogen bond donors and acceptors, respectively. Contrarily to the most widely accepted mechanism through initial Knoevenagel condensation, the most favorable reaction pathway consists of an aldolic reaction between reagents followed by heterocyclization, subsequent dehydration, and, finally, the Michael addition of the second molecule of ethyl cyanoacetate (3) to yield the chromenes 1.

  1. Friedel–Crafts Crosslinked Highly Sulfonated Polyether Ether Ketone (SPEEK) Membranes for a Vanadium/Air Redox Flow Battery

    PubMed Central

    Merle, Géraldine; Ioana, Filipoi Carmen; Demco, Dan Eugen; Saakes, Michel; Hosseiny, Seyed Schwan

    2014-01-01

    Highly conductive and low vanadium permeable crosslinked sulfonated poly(ether ether ketone) (cSPEEK) membranes were prepared by electrophilic aromatic substitution for a Vanadium/Air Redox Flow Battery (Vanadium/Air-RFB) application. Membranes were synthesized from ethanol solution and crosslinked under different temperatures with 1,4-benzenedimethanol and ZnCl2 via the Friedel–Crafts crosslinking route. The crosslinking mechanism under different temperatures indicated two crosslinking pathways: (a) crosslinking on the sulfonic acid groups; and (b) crosslinking on the backbone. It was observed that membranes crosslinked at a temperature of 150 °C lead to low proton conductive membranes, whereas an increase in crosslinking temperature and time would lead to high proton conductive membranes. High temperature crosslinking also resulted in an increase in anisotropy and water diffusion. Furthermore, the membranes were investigated for a Vanadium/Air Redox Flow Battery application. Membranes crosslinked at 200 °C for 30 min with a molar ratio between 2:1 (mol repeat unit:mol benzenedimethanol) showed a proton conductivity of 27.9 mS/cm and a 100 times lower VO2+ crossover compared to Nafion. PMID:24957118

  2. Synthesis and properties of reprocessable sulfonated polyimides cross-linked via acid stimulation for use as proton exchange membranes

    NASA Astrophysics Data System (ADS)

    Zhang, Boping; Ni, Jiangpeng; Xiang, Xiongzhi; Wang, Lei; Chen, Yongming

    2017-01-01

    Cross-linked sulfonated polyimides are one of the most promising materials for proton exchange membrane (PEM) applications. However, these cross-linked membranes are difficult to reprocess because they are insoluble. In this study, a series of cross-linkable sulfonated polyimides with flexible pendant alkyl side chains containing trimethoxysilyl groups is successfully synthesized. The cross-linkable polymers are highly soluble in common solvents and can be used to prepare tough and smooth films. Before the cross-linking reaction is complete, the membranes can be reprocessed, and the recovery rate of the prepared films falls within an acceptable range. The cross-linked membranes are obtained rapidly when the cross-linkable membranes are immersed in an acid solution, yielding a cross-linking density of the gel fraction of greater than 90%. The cross-linked membranes exhibit high proton conductivities and tensile strengths under hydrous conditions. Compared with those of pristine membranes, the oxidative and hydrolytic stabilities of the cross-linked membranes are significantly higher. The CSPI-70 membrane shows considerable power density in a direct methanol fuel cell (DMFC) test. All of these results suggest that the prepared cross-linked membranes have great potential for applications in proton exchange membrane fuel cells.

  3. Iron-Catalyzed Cross-Coupling of Unactivated, Secondary Alkyl Thio Ethers and Sulfones with Aryl Grignard Reagents

    PubMed Central

    Denmark, Scott E.; Cresswell, Alexander J.

    2013-01-01

    The first systematic investigation of unactivated aliphatic sulfur compounds as electrophiles in transition metal-catalyzed cross-coupling are described. Initial studies focused on discerning the structural and electronic features of the organosulfur substrate which enable the challenging oxidative addition to the C(sp3)–S bond. Through extensive optimization efforts, an Fe(acac)3-catalyzed cross-coupling of unactivated alkyl aryl thio ethers with aryl Grignard reagents was realized, in which a nitrogen “directing group” on the S-aryl moiety of the thio ether served a critical role in facilitating the oxidative addition step. In addition, alkyl phenyl sulfones were found to be effective electrophiles in the Fe(acac)3-catalyzed cross-coupling with aryl Grignard reagents. For the latter class of electrophile, a thorough assessment of the various reaction parameters revealed a dramatic enhancement in reaction efficiency with an excess of TMEDA (8.0 equiv). The optimized reaction protocol was used to evaluate the scope of the method with respect to both the organomagnesium nucleophile and sulfone electrophile. PMID:24256193

  4. Friedel-Crafts Crosslinked Highly Sulfonated Polyether Ether Ketone (SPEEK) Membranes for a Vanadium/Air Redox Flow Battery.

    PubMed

    Merle, Géraldine; Ioana, Filipoi Carmen; Demco, Dan Eugen; Saakes, Michel; Hosseiny, Seyed Schwan

    2013-12-30

    Highly conductive and low vanadium permeable crosslinked sulfonated poly(ether ether ketone) (cSPEEK) membranes were prepared by electrophilic aromatic substitution for a Vanadium/Air Redox Flow Battery (Vanadium/Air-RFB) application. Membranes were synthesized from ethanol solution and crosslinked under different temperatures with 1,4-benzenedimethanol and ZnCl2 via the Friedel-Crafts crosslinking route. The crosslinking mechanism under different temperatures indicated two crosslinking pathways: (a) crosslinking on the sulfonic acid groups; and (b) crosslinking on the backbone. It was observed that membranes crosslinked at a temperature of 150 °C lead to low proton conductive membranes, whereas an increase in crosslinking temperature and time would lead to high proton conductive membranes. High temperature crosslinking also resulted in an increase in anisotropy and water diffusion. Furthermore, the membranes were investigated for a Vanadium/Air Redox Flow Battery application. Membranes crosslinked at 200 °C for 30 min with a molar ratio between 2:1 (mol repeat unit:mol benzenedimethanol) showed a proton conductivity of 27.9 mS/cm and a 100 times lower VO2+ crossover compared to Nafion.

  5. Novel proton exchange membranes based on cardo poly(arylene ether sulfone/nitrile)s with perfluoroalkyl sulfonic acid moieties for passive direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Zheng, Jifu; He, Qingyi; Gao, Nian; Yuan, Ting; Zhang, Suobo; Yang, Hui

    2014-09-01

    A new series of cardo poly(arylene ether sulfone/nitrile)s FSPES-x with perfluoroalkyl sulfonic acid groups have been successfully prepared by the perfluorosulfonic acid lactone ring-opening reaction without using any metal or base catalysts. These materials have been characterized by IR, NMR and TGA. The results indicate that this simple and metal-free method of preparation is highly efficient for controlling both the degree of perfluorosulfonation and the position of the sulfonate group and no side reactions such as crosslinking is observed. The FSPES-x membranes (IEC = 1.17-1.64 m equiv g-1) show the desired characteristics such as good film-forming ability, excellent thermal and mechanical properties, low methanol permeability, high conductivity (up to 0.083 S cm-1 at room temperature), as well as appropriate cell performance compared to Nafion®117. With these properties, such fluorinated sulfonic acid side-chain-type polymers are promising PEM materials for application in fuel cells.

  6. Supramolecular motifs in s-block metal-bound sulfonated monoazo dyes, part 1: structural class controlled by cation type and modulated by sulfonate aryl ring position.

    PubMed

    Kennedy, Alan R; Kirkhouse, Jennifer B A; McCarney, Karen M; Puissegur, Olivier; Smith, W Ewen; Staunton, Edward; Teat, Simon J; Cherryman, Julian C; James, Rachel

    2004-09-20

    The solid-state structures of 43 Li, Na, K, Rb, Mg, Ca and Ba salts of para- and meta-sulfonated azo dyes have been examined and can be categorised into three structural classes. All form alternating organic and inorganic layers, however, the nature of the coordination network that forms these layers differs from class to class. The class of structure formed was found to be primarily governed by metal type, but can also be influenced by the nature and position of the organic substituents. Thus, for the para-sulfonated azo dyes, Mg compounds form solvent-separated ion-pair solids; Ca, Ba and Li compounds form simple coordination networks based on metal-sulfonate bonding; and Na, K and Rb compounds form more complex, higher dimensional coordination networks. Compounds of meta-sulfonated azo dyes follow a similar pattern, but here, Ca species may also form solvent-separated ion-pair solids. Significantly, this first attempt to classify such dyestuffs using the principles of supramolecular chemistry succeeds not only for the simple dyes used here as model compounds, but also for more complex molecules, similar to modern colourants.

  7. Organic/inorganic hybrid amine and sulfonic acid tethered silica materials: Synthesis, characterization and application

    NASA Astrophysics Data System (ADS)

    Hicks, Jason Christopher

    The major goals of this thesis were to: (1) create a site-isolated aminosilica material with higher amine loadings than previously reported isolation methods, (2) use spectroscopic, reactivity, and catalytic (olefin polymerization precatalysts) probes to determine isolation of amine groups on these organic/inorganic hybrid materials, (3) synthesize an organic/inorganic hybrid material capable of activating Group 4 olefin polymerization precatalysts, and (4) synthesize a high amine loaded organic/inorganic hybrid material capable of reversibly capturing CO2 in a simulated flue gas stream. The underlying motivation of this research involved the synthesis and design of novel amine and sulfonic acid materials. Traditional routes to synthesize aminosilicas have led to the formation of a high loading of multiple types of amine sites on the silica surface. Part of this research involved the creation of a new aminosilica material via a protection/deprotection method designed to prevent multiple sites, while maintaining a relatively high loading. As a characterization technique, fluorescence spectroscopy of pyrene-based fluorophores loaded on traditional aminosilicas and site-isolated aminosilicas was used to probe the degree of site-isolation obtained with these methods. Also, this protection/deprotection method was compared to other reported isolation techniques with heterogeneous Group 4 constrained-geometry inspired catalysts (CGCs). It was determined that the degree of separation of the amine sites could be controlled with protection/deprotection methods. Furthermore, an increase in the reactivity of the amines and the catalytic activity of CGCs built off of the amines was determined for aminosilicas synthesized by a protection/deprotection method. The second part of this work involved developing organic/inorganic hybrid materials as heterogeneous Bronsted acidic cocatalysts for activation of olefin polymerization precatalysts. This was the first reported organic

  8. Phosphoric Acid-Mediated Synthesis of Vinyl Sulfones through Decarboxylative Coupling Reactions of Sodium Sulfinates with Phenylpropiolic Acids.

    PubMed

    Rong, Guangwei; Mao, Jincheng; Yan, Hong; Zheng, Yang; Zhang, Guoqi

    2015-08-07

    A novel phosphoric acid -mediated synthesis of vinyl sulfones through decarboxylative coupling reactions of sodium sulfinates with phenylpropiolic acids is described. This transformation is efficient and environmentally friendly.

  9. EFFECT OF THE CATION ON SOLUBILIZATION BY OIL-SOLUBLE SULFONATES AND THE APPLICABILITY OF THE MASS LAW,

    DTIC Science & Technology

    SURFACE ACTIVE SUBSTANCES, *SULFONATES), ORGANIC SOLVENTS, SOLUBILITY, COLLOIDS, CESIUM COMPOUNDS, SODIUM COMPOUNDS, BARIUM COMPOUNDS, MAGNESIUM COMPOUNDS, ZINC COMPOUNDS, CARBINOLS, AMINES, ACETIC ACID , TOLUENES, GAS CHROMATOGRAPHY, MOLECULAR ASSOCIATION

  10. Direct electrochemical DNA detection originated from the self-redox signal of sulfonated polyaniline enhanced by graphene oxide in neutral solution.

    PubMed

    Yang, Tao; Meng, Le; Wang, Xinxing; Wang, Longlong; Jiao, Kui

    2013-11-13

    In this paper, a type of direct DNA impedance detection using the self-redox signal change of sulfonated polyaniline (SPAN) enhanced by graphene oxide (GNO) was reported, here SPAN is a copolymer obtained from aniline and m-aminobenzenesulfonic acid. The resulting nanocomposite was characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. The π-π planar structure of GNO and the carboxyl groups on the surface of GNO ensured it could act as an excellent substrate for adsorption and polymerization of aniline monomer. Because of the existence of GNO, the electrochemical activities of SPAN were enhanced obviously. Because of abundant sulfonic acid groups, the resulting nanocomposite showed obvious self-redox signal even at physiological pH, which is beneficial for biosensing field. DNA probes with amine groups could be covalently attached to the modified electrode surface through the acyl chloride cross-linking reaction of sulfonic groups and amines. When the flexible probe DNA was successfully grafted, the electrode was coated and electron transfer between electrode and buffer was restrained. Thus, the inner impedance value of SPAN (rather than using outer classic EIS probe, [Fe(CN)6](3-/4-)) increased significantly. After hybridization, the rigid helix opened the electron channel, which induced impedance value decreased dramatically. As an initial application of this system, the PML/RARA fusion gene sequence formed from promyelocytic leukemia (PML) and retinoic acid receptor alpha (RARA) was successfully detected.

  11. Separation and fragmentation study of isocoproporphyrin derivatives by UHPLC-ESI-exact mass MS/MS and identification of a new isocoproporphyrin sulfonic acid metabolite.

    PubMed

    Benton, Christopher M; Lim, Chang Kee; Moniz, Caje; Baxter, Sinéad L; Jones, Donald J L

    2014-01-01

    Isocoproporphyrin and its derivatives are commonly used as biomarkers of porphyria cutanea tarda, heavy metal toxicity and hexachlorobenzene (HCB) intoxication in humans and animals. However, most are isobaric with other porphyrins and reference materials are unavailable commercially. The structural characterisation of these porphyrins is important but very little data is available. We report here the separation and characterisation of isocoproporphyrin, deethylisocoproporphyrin, hydroxyisocoproporphyrin and ketoisocoproporphyrin, isolated in the faeces of rats fed with a diet containing HCB, by ultra high performance liquid chromatography-exact mass tandem mass spectrometry (UHPLC-MS/MS). Furthermore, we report the identification and characterisation of a previously unreported porphyrin metabolite, isocoproporphyrin sulfonic acid isolated in the rat faeces. The measured mass-to-charge ratio (m/z) of the precursor ion was m/z 735.2338, corresponding to a molecular formula of C36H39N4O11S with an error of 0.3 ppm from the calculated m/z 735.2336. The MS/MS data was consistent with an isocoproporphyrin sulfonic acid structure, derived from dehydroisocoproporphyrinogen by sulfonation of the vinyl group. The metabolite was present in a greater abundance than other isocoproporphyrin derivatives and may be a more useful biomarker for HCB intoxication.

  12. Synthesis Of [2h, 13c]M [2h2m 13c], And [2h3,, 13c] Methyl Aryl Sulfones And Sulfoxides

    DOEpatents

    Martinez, Rodolfo A.; Alvarez, Marc A.; Silks, III, Louis A.; Unkefer, Clifford J.; Schmidt, Jurgen G.

    2004-07-20

    The present invention is directed to labeled compounds, [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2, .sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfones and [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2, .sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfoxides, wherein the .sup.13 C methyl group attached to the sulfur of the sulfone or sulfoxide includes exactly one, two or three deuterium atoms and the aryl group is selected from the group consisting of 1-naphthyl, substituted 1-naphthyl, 2-naphthyl, substituted 2-naphthyl, and phenyl groups with the structure: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each independently, hydrogen, a C.sub.1 -C.sub.4 lower alkyl, a halogen, an amino group from the group consisting of NH.sub.2, NHR and NRR' where R and R' are each a C.sub.1 -C.sub.4 lower alkyl, a phenyl, or an alkoxy group. The present invention is also directed to processes of preparing methyl aryl sulfones and methyl aryl sulfoxides.

  13. Preparation of Pt/polypyrrole-para toluene sulfonate hydrogen peroxide sensitive electrode for the utilizing as a biosensor.

    PubMed

    Çete, Servet; Bal, Özgür

    2013-12-01

    A film electrode with electropolymerization of pyrrole (Py) and para-toluene sulfonate (pTS) as a anionic dopant is prepared and its sensitivity to hydrogen peroxide is investigated. The polypyrrole is deposited on a 0.5 cm(2) Pt plate an electrochemically prepared pTS ion-doped polypyrrole film by scanning the electrode potential between - 0.8 and + 0.8 V at a scan rate of 20 mV/s. The electrode's sensitivity to hydrogen peroxide is investigated at room temperature using 0.1 M phosphate buffer at pH 7.5. The working potential is found as a 0.3 V. The concentrations of pyrrole and pTS are 50mM M and 25 mM. Polypyrrole was coated on the electrode surface within 10 cycles. İmmobilization of glucose oxidase carried out on Pt/polypyrrole-para toluene sulfonate (Pt/PPy-pTS) film by cross-linking with glutaraldehyde. The morphology of electrodes was characterized by SEM and AFM. Moreover, contact angle measurements were made with 1 μL water of polymer film and enzyme electrode. It has shown that enzyme electrode is very sensitive against to glucose.

  14. Degradation of poly(ether sulfone)/polyvinylpyrrolidone membranes by sodium hypochlorite: insight from advanced electrokinetic characterizations.

    PubMed

    Hanafi, Yamina; Szymczyk, Anthony; Rabiller-Baudry, Murielle; Baddari, Kamel

    2014-11-18

    Poly(ether sulfone) (PES)/polyvinylpyrrolidone (PVP) membranes are widely used in various industrial fields such as drinking water production and in the dairy industry. However, the use of oxidants to sanitize the processing equipment is known to impair the integrity and lifespan of polymer membranes. In this work we showed how thorough electrokinetic measurements can provide essential information regarding the mechanism of degradation of PES/PVP membranes by sodium hypochlorite. Tangential streaming current measurements were performed with ultrafiltration and nanofiltration PES/PVP membranes for various aging times. The electrokinetic characterization of membranes was complemented by FTIR-ATR spectroscopy. Results confirmed that sodium hypochlorite induces the degradation of both PES and PVP. This latter is easily oxidized by sodium hypochlorite, which leads to an increase in the negative charge density of the membrane due to the formation of carboxylic acid groups. The PVP was also found to be partly released from the membrane with aging time. Thanks to the advanced electrokinetic characterization implemented in this work it was possible for the first time to demonstrate that two different mechanisms are involved in the degradation of PES. Phenol groups were first formed as a result of the oxidation of PES aromatic rings by substitution of hydrogen by hydroxyl radicals. For more severe aging conditions, this membrane degradation mechanism was followed by the formation of sulfonic acid functions, thus indicating a second degradation process through scission of PES chains.

  15. Preparation of a carbon-based solid acid catalyst by sulfonating activated carbon in a chemical reduction process.

    PubMed

    Liu, Xiao-Yan; Huang, Miao; Ma, Hai-Long; Zhang, Zeng-Qiang; Gao, Jin-Ming; Zhu, Yu-Lei; Han, Xiao-Jin; Guo, Xiang-Yun

    2010-10-18

    Sulfonated (SO(3)H-bearing) activated carbon (AC-SO(3)H) was synthesized by an aryl diazonium salt reduction process. The obtained material had a SO(3)H density of 0.64 mmol·g-1 and a specific surface area of 602 m2·g-1. The catalytic properties of AC-SO(3)H were compared with that of two commercial solid acid catalysts, Nafion NR50 and Amberlyst-15. In a 10-h esterification reaction of acetic acid with ethanol, the acid conversion with AC-SO(3)H (78%) was lower than that of Amberlyst-15 (86%), which could be attributed to the fact that the SO(3)H density of the sulfonated carbon was lower than that of Amberlyst-15 (4.60 mmol·g-1). However, AC-SO(3)H exhibited comparable and even much higher catalytic activities than the commercial catalysts in the esterification of aliphatic acids with longer carbon chains such as hexanoic acid and decanoic acid, which may be due to the large specific surface area and mesoporous structures of the activated carbon. The disadvantage of AC-SO(3)H is the leaching of SO(3)H group during the reactions.

  16. Bis(4-chlorophenyl) sulfone (BCPS) in Swedish marine and fresh water wildlife-a screening study.

    PubMed

    Norström, Karin; Olsson, Anders; Olsson, Mats; Bergman, Ake

    2004-07-01

    Bis(4-chlorophenyl) sulfone (BCPS) is a high production volume chemical (HPVC) applied in thermostable polymers. BCPS has been detected as an environmental contaminant both in Europe and in North America but it is still not a commonly studied pollutant. In this study, three Baltic Sea fish species; herring (Clupea harengus), salmon (Salmo salar) and perch (Perca fluviatilis) from the Swedish coast, and one inland fish species, arctic char (Salvelinus alpinus), were analysed to screen for the occurrence and distribution of BCPS. Salmon and arctic char, were sampled in the early 1970s as well as the late 1990s. Fish eating grey seal (Halichoerus gryphus) and guillemot (Uria aalge) from the Baltic Sea were included to screen for whether BCPS biomagnify or not. The representativeness of the analysed samples for studying bioaccumulation of environmental pollutants was compared through analysis of two well known persistent and bioaccumulating compounds, 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), and 4,4'-DDE. Pooled muscle and blubber samples based on 4-10 individuals were used for analysis, as well as individual samples of grey seal blubber. 2,4,4'-Trichlorodiphenyl sulfone, was synthesised and applied as an internal standard. BCPS was detected in all marine samples but in only one of the fresh water fish samples. The highest BCPS concentrations detected, 1600 and 1900 ng/g lipid weighet (l.w.), were found in muscle from Baltic guillemot. The results indicate that BCPS is bioaccumulated in both grey seal and guillemot, and that the guillemot has higher concentrations of BCPS than the grey seal (50-500 ng/g l.w.). The concentrations found in different species of fish from the Baltic Sea ranged between 15-37 ng/g l.w. and lower concentrations were found in freshwater species (n.d.-1.8 ng/g l.w.). The present study shows that BCPS is found in all investigated species of wildlife but, in most species, still at low concentrations. However, the guillemot has levels in the

  17. Coumarin sulfonates: As potential leads for ROS inhibition.

    PubMed

    Salar, Uzma; Khan, Khalid Mohammed; Jabeen, Almas; Faheem, Aisha; Fakhri, Muhammad Imran; Saad, Syed Muhammad; Perveen, Shahnaz; Taha, Muhammad; Hameed, Abdul

    2016-12-01

    Coumarin sulfonates 4-43 were synthesized by reacting 3-hydroxy coumarin 1, 4-hydroxy coumarin 2and6-hydroxy coumarin 3 with different substituted sulfonyl chlorides and subjected to evaluate for their in vitro immunomodulatory potential. The compounds were investigated for their effect on oxidative burst activity of zymosan stimulated whole blood phagocytes using a luminol enhanced chemiluminescence technique. Ibuprofen was used as standard drug (IC50=54.2±9.2μM). Eleven compounds 6 (IC50=46.60±14.6μM), 8 (IC50=11.50±6.5μM), 15 (IC50=21.40±12.2μM), 19 (IC50=5.75±0.86μM), 22 (IC50=10.27±1.06μM), 23 (IC50=33.09±5.61μM), 24 (IC50=4.93±0.58μM), 25 (IC50=21.96±14.74μM), 29 (IC50=12.47±9.2μM), 35 (IC50=20.20±13.4μM) and 37 (IC50=14.47±5.02μM) out of forty demonstrated their potential suppressive effect on production of reactive oxygen species (ROS) as compared to ibuprofen. All the synthetic derivatives 4-43 were characterized by different available spectroscopic techniques such as (1)H NMR, (13)C NMR, EIMS and HRMS. CHN analysis was also performed.

  18. Determination of the adsorption model of alkenes and alcohols on sulfonic copolymer by inverse gas chromatography.

    PubMed

    Słomkiewicz, P M

    2004-04-23

    The determination of a number of adsorption sites on sulfonated styrene-divinylbenzene copolymer for alkenes (propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, isobutene, 2-methyl-1-butene, 2-methyl-2-butene, 2-methyl-1-pentene, 2-methyl-2-pentene and 2-methyl-2-hexene) and alcohols (methanol, ethanol and n-propanol, n-butanol, 2-butanol and tert-butanol) was performed by the saturation copolymer with vapors of adsorbate, by removing the excess of adsorbate from copolymer by blowing the inert gas through copolymer bed and by the desorption of adsorbed alcohol in the programmed increase of temperature. The adsorption measurements were performed on sulfonated ion-exchange resin (Amberlyst 15) with different concentrations of the acid group, which means with a varying number of adsorption sites. The following adsorption models for alkenes were suggested: the first in which one molecule of alkene is adsorbed by two sulfonic groups, for linear alcohols, the second in which one sulfonic group can adsorb one molecule of alcohol and for non-linear alcohols the third where one molecule of alcohol is adsorbed by two or more sulfonic groups.

  19. Copoly(arlene ether)s containing pendant sulfonic acid groups as proton exchange membrane

    SciTech Connect

    Kim, Yu Seung; Kim, Dae Sik; Robertson, Gilles; Guiver, Michael

    2008-01-01

    A copoly(arylene ether) (PAE) with high fluorine content and a copoly(arylene ether nitrile) (PAEN) with high nitrile content, each containing pendant phenyl sulfonic acids were synthesized. The P AE and PAEN were prepared from decafluorobiphenyl (DFBP) and difluorobenzonitrile (DFBN) respectively, by polycondensation with 2-phenylhydroquinone (PHQ) by conventional aromatic nucleophilic substitution reactions. The sulfonic acid groups were introduced by mild post-sulfonation exclusively on the para-position of the pendant phenyl ring in PHQ. The membrane properties of the resulting sulfonated copolymers sP AE and sP AEN were compared for fuel cell applications. The copolymers sPAE and sPAEN, each having a degree of sulfonation (DS) of 1.0 had high ion exchange capacities (IEC{sub v}(wet) (volume-based, wet state)) of 1.77 and 2.55 meq./cm{sup 3}, high proton conductivities of 135.4 and 140.1 mS/cm at 80 C, and acceptable volume-based water uptake of 44.5-51.9 vol% at 80 C, respectively, compared to Nafion. The data points of these copolymer membranes are located in the area of outstanding properties in the trade-off plot of alternative hydrocarbon polyelectrolyte membranes (PEM) for the relationship between proton conductivity versus water uptake (weight based or volume based). Furthermore, the relative selectivity derived from proton conductivity and methanol permeability is higher than that of Nafion.

  20. Perfluorooctane sulfonate (PFOS) contamination of fish in urban lakes: a prioritization methodology for lake management.

    PubMed

    Xiao, Feng; Gulliver, John S; Simcik, Matt F

    2013-12-15

    The contamination of urban lakes by anthropogenic pollutants such as perfluorooctane sulfonate (PFOS) is a worldwide environmental problem. Large-scale, long-term monitoring of urban lakes requires careful prioritization of available resources, focusing efforts on potentially impaired lakes. Herein, a database of PFOS concentrations in 304 fish caught from 28 urban lakes was used for development of an urban-lake prioritization framework by means of exploratory data analysis (EDA) with the aid of a geographical information system. The prioritization scheme consists of three main tiers: preliminary classification, carried out by hierarchical cluster analysis; predictor screening, fulfilled by a regression tree method; and model development by means of a neural network. The predictive performance of the newly developed model was assessed using a training/validation splitting method and determined by an external validation set. The application of the model in the U.S. state of Minnesota identified 40 urban lakes that may contain elevated levels of PFOS; these lakes were not previously considered in PFOS monitoring programs. The model results also highlight ongoing industrial/commercial activities as a principal determinant of PFOS pollution in urban lakes, and suggest vehicular traffic as an important source and surface runoff as a primary pollution carrier. In addition, the EDA approach was further compared to a spatial interpolation method (kriging), and their advantages and disadvantages were discussed.

  1. Colorimetric detection of Cd2+ using 1-amino-2-naphthol-4-sulfonic acid functionalized silver nanoparticles

    NASA Astrophysics Data System (ADS)

    Huang, Pengcheng; Liu, Bowen; Jin, Weiwei; Wu, Fangying; Wan, Yiqun

    2016-11-01

    A colorimetric assay has been developed for facile, rapid, and sensitive detection of Cd2+ using 1-amino-2-naphthol-4-sulfonic acid functionalized silver nanoparticles (ANS-AgNPs). The presence of Cd2+ induces the aggregation of ANS-AgNPs through cooperative metal-ligand interaction. As a result, the characteristic surface plasmon resonance (SPR) peak of ANS-AgNPs at 390 nm was red-shifted to 580 nm, yielding a color change from bright yellow to reddish-brown. The color change is monitored by UV-Vis spectrometer and can be directly read out by the naked eye. Under the optimized conditions, a good linear relationship (correlation coefficient R = 0.997) was obtained between the ratio of the absorbance at 580 nm to that at 390 nm (A580nm/A390nm) and the concentration of Cd2+ over the range of 1.0-10 μM with detection limit of 87 nM. The proposed method is simple and efficient, which has been applied for determining Cd2+ in milk powder, serum, and lake water with satisfactory results.

  2. High proton-conducting organic/inorganic nanocomposite films based on sulfonated polystyrene-block-poly(ethyl-ran-propylene)-block-polystyrene and silica nanoparticles.

    PubMed

    Jang, Suk-Yong; Han, Sien-Ho

    2013-12-01

    Sulfonated polystyrene-block-poly(ethyl-ran-propylene)-block-polystyrene (S-polySEPS) was prepared by sulfonation at the phenyl groups of the polystyrene-block-poly(ethyl-ran-propylene)-block-polystyrene (polySEPS) containing 65% styrene groups for proton exchange membrane. High proton-conducting S-polySEPS/silica nanocomposite films were produced by direct-mixing of nanosilica particles with the S-polySEPS copolymer. The TEM image of the S-polySEPS/silica nanocomposite films showed that the silica particles were very-well dispersed within the S-polySEPS matrix. Also, the XRD patterns showed the presence of the nano-scaled silica particles. Moreover, the nano-scaled silica particles played an important role in the prepared organic/inorganic nanocomposite properties such as proton conductivity, thermal stability, water content and ion exchange capacity (IEC). The S-polySEPS/silica 1 wt% (1.41 x 10(-1) S/cm) and 2 wt% (9.9 x 10(-2) S/cm) nanocomposite films had higher proton conductivity than Nafion 117 (9.8 x 10(-2) S/cm) at the temperature of 90 degrees C. The FT-IR analysis was used to verify the sulfonation of the S-polySEPS copolymer. The TGA analysis was carried out to investigate the thermal stability of the S-polySEPS/silica nanocomposite films.

  3. A novel SPE-HPLC method for simultaneous determination of selected sulfonated phthalocyanine zinc complexes in mouse plasma following cassette dosing.

    PubMed

    Jiang, Zhou; Shao, Jingwei; Chen, Meili; Wang, Jian; Jia, Lee

    2013-08-07

    Sulfonated phthalocyanine zinc complexes (ZnPcSn) are a mixture of polymolecules with different number of the sulfonic groups. They are typical photosensitizers for photodynamic therapy (PDT). Analysis of the sulfonic phthalocyanine complexes in blood is a global technical challenge to developing this kind of photosensitizers into clinics. To circumvent the problem, we aimed at developing a novel solid-phase extraction (SPE)-HPLC method, which was primarily composed of (1) the SPE material that has both the aliphatic benzene group and hydrophilic ethylenediamino group bonded to the silica surface typically for retaining those hydrophobic compounds with some degree of hydrophilic anionic (negatively charged) functionality; and (2) the RP-Amide C16 HPLC column packed with palmitamidopropylsilane for both reversed-phase and anion exchange separation. The method was validated in terms of recovery, precision and accuracy for pharmacokinetic study with the photosensitizer following its intravenous cassette dosing to mice. The present study is the first report on using an SPE-HPLC mode to simultaneously determine the phthalocyanine-based polymolecule photosensitizer in blood. The study will aid in clinical development of photosensitizers.

  4. Leads for development of new naphthalenesulfonate derivatives with enhanced antiangiogenic activity: crystal structure of acidic fibroblast growth factor in complex with 5-amino-2-naphthalene sulfonate.

    PubMed

    Fernández-Tornero, Carlos; Lozano, Rosa M; Redondo-Horcajo, Mariano; Gómez, Ana M; López, José C; Quesada, Ernesto; Uriel, Clara; Valverde, Serafín; Cuevas, Pedro; Romero, Antonio; Giménez-Gallego, Guillermo

    2003-06-13

    Inhibition of angiogenesis-promoting factors such as fibroblast growth factors is considered to be a potential procedure for inhibiting solid tumor growth. Although several peptide-based inhibitors are currently under study, the development of antiangiogenic compounds of small molecular size is a pharmacological goal of considerable interest. We have already shown that certain naphthalene sulfonates constitute minimal functional substitutes of the antiangiogenic compounds of the suramin and suradista family. Using those data as a lead, we have carried out a rational search for new angiogenesis inhibitors that could provide new pharmacological insights for the development of antiangiogenic treatments. The results of the study strongly underline the relevance of the stereochemistry for an efficient inhibition of acidic fibroblast growth factor mitogenic activity by the naphthalene sulfonate family and allow us to formulate rules to aid in searching for new inhibitors and pharmaceutical developments. To provide further leads for such developments and acquire a detailed insight into the basis of the inhibitory activity of the naphthalene sulfonate derivatives, we solved the three-dimensional structure of acidic fibroblast growth factor complexed to 5-amino-2-naphthalenesulfonate, the most pharmacologically promising of the identified inhibitors. The structure shows that binding of this compound would hamper the interaction of acidic fibroblast growth factor with the different components of the cell membrane mitogenesis-triggering complex.

  5. Sodium dodecyl benzene sulfonate-assisted synthesis through a hydrothermal reaction

    SciTech Connect

    Sobhani, Azam; Salavati-Niasari, Masoud

    2012-08-15

    Graphical abstract: Reaction of a SeCl{sub 4} aqueous solution with a NiCl{sub 2}·6H{sub 2}O aqueous solution in presence of sodium dodecyl benzene sulfonate (SDBS) as capping agent and hydrazine (N{sub 2}H{sub 4}·H{sub 2}O) as reductant, produces nanosized nickel selenide through a hydrothermal method. The effect of temperature, reaction time and amounts of reductant on the morphology, particle sizes of NiSe nanostructures has been investigated. Highlights: ► NiSe nanostructures were synthesized by hydrothermal method. ► A novel Se source was used to synthesize NiSe. ► SDBS as capping agent plays a crucial role on the morphology of products. ► A mixture of Ni{sub 3}Se{sub 2} and NiSe was prepared in the presence of 2 ml hydrazine. ► A pure phase of NiSe was prepared in the presence of 4 or 6 ml hydrazine. -- Abstract: The effects of the anionic surfactant on the morphology, size and crystallization of NiSe precipitated from NiCl{sub 2}·6H{sub 2}O and SeCl{sub 4} in presence of hydrazine (N{sub 2}H{sub 4}·H{sub 2}O) as reductant were investigated. The products have been successfully synthesized in presence of sodium dodecyl benzene sulfonate (SDBS) as surfactant via an improved hydrothermal route. A variety of synthesis parameters, such as reaction time and temperature, capping agent and amount of reducing agent have a significant effect on the particle size, phase purity and morphology of the obtained products. The sample size became bigger with decreasing reaction temperature and increasing reaction time. In the presence of 2 ml hydrazine, the samples were found to be the mixture of Ni{sub 3}Se{sub 2} and NiSe. With increasing the reaction time and amount of hydrazine a pure phase of hexagonal NiSe was obtained. X-ray diffraction analysis (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) images indicate phase, particle size and morphology of the products. Chemical composition and purity of the products were

  6. Non-classical azoreductase secretion in Clostridium perfringens in response to sulfonated azo dye exposure.

    PubMed

    Morrison, Jessica M; John, Gilbert H

    2015-08-01

    Clostridium perfringens, a strictly anaerobic microorganism and inhabitant of the human intestine, has been shown to produce an azoreductase enzyme (AzoC), an NADH-dependent flavin oxidoreductase. This enzyme reduces azo dyes into aromatic amines, which can be carcinogenic. A significant amount of work has been completed on the activity of AzoC. Despite this, much is still unknown, including whether azoreduction of these dyes occurs intracellularly or extracellulary. A physiological study of C. perfringens involving the effect of azo dye exposure was completed to answer this question. Through exposure studies, azo dyes were found to cause cytoplasmic protein release, including AzoC, from C. perfringens in dividing and non-dividing cells. Sulfonation (negative charge) of azo dyes proved to be the key to facilitating protein release of AzoC and was found to be azo-dye-concentration-dependent. Additionally, AzoC was found to localize to the Gram-positive periplasmic region. Using a ΔazoC knockout mutant, the presence of additional azoreductases in C. perfringens was suggested. These results support the notion that the azoreduction of these dyes may occur extracellularly for the commensal C. perfringens in the intestine.

  7. Toxicity and DNA methylation changes induced by perfluorooctane sulfonate (PFOS) in sea urchin Glyptocidaris crenularis.

    PubMed

    Ding, Guanghui; Wang, Luyan; Zhang, Jing; Wei, Yuanyuan; Wei, Lie; Li, Yang; Shao, Mihua; Xiong, Deqi

    2015-06-01

    Perfluorooctane sulfonate (PFOS) is an ubiquitous persistent organic pollutant, which can be bioaccumulated and cause adverse effects on organisms. However, there is very limited information about the toxic effects of PFOS to marine organisms and its mechanisms. Therefore, in the present study, adult sea urchins Glyptocidaris crenularis were exposed to PFOS for 21 d, followed by a 7-d depuration period, in order to investigate the toxicity of PFOS to sea urchin and its potential epigenetic mechanisms. Sea urchins dropped spines, and lowered down the motor ability and feeding ability after the PFOS exposure. Superoxide dismutase activities in supernatant of coelomic fluid of sea urchin increased firstly and then dropped down, while the change of the catalase activity took an opposite trend during the exposure period. They both approached to the corresponding activity of the control after the depuration period. The DNA methylation polymorphism, methylation rate and demethylation rate in sea urchin gonad all increased following the prolonged exposure time, and then decreased after the depuration period. The demethylation rates were lower than the corresponding methylation rates, therefore methylation events were dominant during the whole experimental period. This might suggest that sea urchin have strong self-protection mechanisms and can survive from the PFOS exposure presented in this study. Further efforts are needed to more precisely investigate the DNA methylation effects of PFOS and the self-protection mechanism of sea urchin.

  8. Spontaneous modification of graphite anode by anthraquinone-2-sulfonic acid for microbial fuel cells.

    PubMed

    Tang, Xinhua; Li, Haoran; Du, Zhuwei; Ng, How Yong

    2014-07-01

    In this study, anthraquinone-2-sulfonic acid (AQS), an electron transfer mediator, was immobilized onto graphite felt surface via spontaneous reduction of the in situ generated AQS diazonium cations. Cyclic voltammetry (CV) and energy dispersive spectrometry (EDS) characterizations of AQS modified graphite demonstrated that AQS was covalently grafted onto the graphite surface. The modified graphite, with a surface AQS concentration of 5.37 ± 1.15 × 10(-9)mol/cm(2), exhibited good electrochemical activity and high stability. The midpoint potential of the modified graphite was about -0.248 V (vs. normal hydrogen electrode, NHE), indicating that electrons could be easily transferred from NADH in bacteria to the electrode. AQS modified anode in MFCs increased the maximum power density from 967 ± 33 mW/m(2) to 1872 ± 42 mW/m(2). These results demonstrated that covalently modified AQS functioned as an electron transfer mediator to facilitate extracellular electron transfer from bacteria to electrode and significantly enhanced the power production in MFCs.

  9. Aquatic predicted no-effect-concentration derivation for perfluorooctane sulfonic acid.

    PubMed

    Qi, Ping; Wang, Ying; Mu, Jingli; Wang, Juying

    2011-04-01

    Perfluorooctane sulfonic acid (PFOS), a representative perfluorinated surfactant, is an anthropogenic pollutant detected in various environmental and biological matrices. Some laboratory and field work has been conducted to assess the aquatic toxicity of PFOS, but little is known regarding its toxicity threshold to the aquatic ecosystem. In the present study, predicted no-effect concentrations (PNECs) were derived by four different approaches. The interspecies correlation estimation (ICE) program and final acute-to-chronic ratio (FACR) were applied to the development of PNEC based on the toxic mode of action (MOA) of PFOS. By comparison of the different PNECs, the recommended aquatic toxicity thresholds for PFOS are in the range of 0.61 to 6.66 µg/L. Based on comparison of PNEC values, microcosm results, and reported environmental concentrations, PFOS appears not to pose a serious threat to aquatic organisms. The present results demonstrate that MOA is an important consideration for the derivation of reliable PNECs; moreover, the ICE-based species sensitivity distribution (SSD) method can be used to derive PNECs when toxicological data are limited. The application of MOA and ICE for deriving PNEC values in the present study may facilitate studies on using a combination of quantitative structure-activity relationship (QSAR) models and ICE to estimate PNECs.

  10. Electrochemical sensor based on polystyrene sulfonate-carbon nanopowders composite for Cu (II) determination.

    PubMed

    Cantalapiedra, Alberto; Gismera, M Jesús; Procopio, Jesús R; Sevilla, M Teresa

    2015-07-01

    A differential pulse anodic stripping voltammetric (DPASV) method, with an open circuit (OC) approach in the pre-concentration step has been developed for copper ion determination at very low concentration level using a sensor based on a polystyrene sulfonate-carbon nanopowders (PSS-CnP) composite. This composite material is easily prepared from ultrasonic assisted dispersions of CnP in aqueous solution of PSS. For preparation of sensor devices, a reproducible and inexpensive drop coating procedure of the surface of home-made pencil graphite electrodes (PGEs) using a CnP dispersion in PSS was performed. At the optimal conditions for accumulation (0.01molL(-1) KNO3 at pH 3) and measurement steps (a reduction potential of -0.5V for 60s and then, an anodic DPV scan) and using a pre-concentration time of 300s, the limit of detection was 0.11µgL(-1) (1.73nM). This OC-DPASV method using the PSS-CnP-PGE sensor was successfully employed for Cu(II) determination in mineral, river and sea water samples.

  11. Crystal structure of potassium (1S)-d-lyxit-1-yl­sulfonate monohydrate

    PubMed Central

    Haines, Alan H.; Hughes, David L.

    2015-01-01

    The title compound, K+·C5H11O8S−·H2O [systematic name: potassium (1S,2S,3S,4R)-1,2,3,4,5-penta­hydroxy­pentane-1-sulfonate monohydrate], formed by reaction of d-lyxose with potassium hydrogen sulfite in water, crystallizes as colourless square prisms. The anion has an open-chain structure in which the S atom, the C atoms of the sugar chain and the oxygen atom of the hy­droxy­methyl group form an essentially all-trans chain with the corresponding torsion angles lying between 178.61 (12) and 157.75 (10)°. A three-dimensional bonding network exists in the crystal structure involving coordination of two crystallographically independent potassium ions by O atoms (one cation being hexa- and the other octa-coordinate, with each lying on a twofold rotation axis), and extensive inter­molecular O—H⋯O hydrogen bonding. PMID:26396774

  12. Synthesis of porous sulfonated carbon as a potential adsorbent for phenol wastewater.

    PubMed

    Prabhu, Azhagapillai; Al Shoaibi, Ahmed; Srinivasakannan, C

    2015-01-01

    The work reports a facile synthesis procedure for preparation of porous sulfonated carbons and its suitability for adsorption of phenol. The sulfonated carbon was synthesized utilizing a simplified, single-step, shorter duration process by sulfonation, dehydration and carbonization of sucrose in sulfuric acid and tetraethylorthosilicate. The surface and internal structures of the adsorbents were characterized utilizing various characterization techniques to understand the porous nature and surface functional groups of the porous matrix. Adsorption capacity was found to be highest for the sample heat treated at 600 °C, with the maximum adsorption capacity of 440 mg/g at 30 °C. The adsorption isotherms were tested with the Freundlich and Langmuir adsorption isotherms models to identify the appropriate adsorption mechanism.

  13. QENS investigation of proton confined motions in hydrated perfluorinated sulfonic membranes and self-assembled surfactants

    NASA Astrophysics Data System (ADS)

    Berrod, Quentin; Lyonnard, Sandrine; Guillermo, Armel; Ollivier, Jacques; Frick, Bernhard; Gébel, Gérard

    2015-01-01

    We report on QuasiElastic Neutron Scattering (QENS) investigations of the dynamics of protons and water molecules confined in nanostructured perfluorinated sulfonic acid (PFSA) materials, namely a commercial Aquivion membrane and the perfluorooctane sulfonic acid (PFOS) surfactant. The former is used as electrolyte in low-temperature fuel cells, while the latter forms mesomorphous self-assembled phases in water. The dynamics was investigated as a function of the hydration level, in a wide time range by combining time-of-flight and backscattering incoherent QENS experiments. Analysis of the quasielastic broadening revealed for both systems the existence of localized translational diffusive motions, fast rotational motions and slow hopping of protons in the vicinity of the sulfonic charges. The characteristic times and diffusion coefficients have been found to exhibit a very similar behaviour in both membrane and surfactant structures. Our study provides a comprehensive picture of the proton motion mechanisms and the dynamics of confined water in model and real PFSA nanostructures.

  14. Polymer electrolyte membranes from fluorinated polyisoprene-block-sulfonated polystyrene: Structural evolution with hydration and heating

    SciTech Connect

    Sodeye, Akinbode; Huang, Tianzi; Gido, Samuel; Mays, Jimmy

    2011-01-01

    Small-angle neutron scattering (SANS) and ultra-small-angle X-ray scattering (USAXS) have been used to study the structural changes in fluorinated polyisoprene/sulfonated polystyrene (FISS) diblock copolymers as they evolved from the dry state to the water swollen state. A dilation of the nanometer-scale hydrophilic domains has been observed as hydration increased, with greater dilation occurring in the more highly sulfonated samples or upon hydration at higher temperatures. Furthermore, a decrease in the order in these phase separated structures is observed upon swelling. The glass transition temperatures of the fluorinated blocks have been observed to decrease upon hydration of these materials, and at the highest hydration levels, differential scanning calorimetry (DSC) has shown the presence of tightly bound water. A precipitous drop in the mechanical integrity of the 50% sulfonated materials is also observed upon exceeding the glass transition temperature (Tg), as measured by dynamic mechanical analysis (DMA).

  15. Low cost brine tolerant sulfonate and sulfate surfactants having 1,3-dyhydrocharboxy-2-propyl hydrophobic tails

    SciTech Connect

    Hoskin, D. H.

    1985-05-07

    Novel sulfonate and sulfate surfactants which have low interfacial tension at high salinity, and their use in enhanced oil recovery are disclosed. These surfactants may be made from relatively inexpensive intermediates, such as monohydric alcohols and epichlorohydrin. These surfactants have 1,3-dihydrocarboxy-2-propyl hydrophobic tails linked by ethoxy linkages to sulfate or alkyl sulfonate moieties.

  16. Bioinformatic Characterization of the 4-Toluene Sulfonate Uptake Permease (TSUP) Family of Transmembrane Proteins

    PubMed Central

    Shlykov, Maksim A.; Zheng, Wei Hao; Chen, Jonathan S.; Saier, Milton H.

    2012-01-01

    The ubiquitous sequence diverse 4-Toluene Sulfonate Uptake Permease (TSUP) family contains few characterized members and is believed to catalyze the transport of several sulfur-based compounds. Prokaryotic members of the TSUP family outnumber the eukaryotic members substantially, and in prokaryotes, but not eukaryotes, extensive lateral gene transfer occurred during family evolution. Despite unequal representation, homologues from the three taxonomic domains of life share well-conserved motifs. We show that the prototypical eight TMS topology arose from an intragenic duplication of a four TMS unit. Possibly, a two TMS α-helical hairpin structure was the precursor of the 4 TMS repeat unit. Genome context analyses confirmed the proposal of a sulfur-based compound transport role for many TSUP homologues, but functional outliers appear to be prevalent as well. Preliminary results suggest that the TSUP family is a member of a large novel superfamily that includes rhodopsins, integral membrane chaperone proteins, transmembrane electron flow carriers and several transporter families. All of these proteins probably arose via the same pathway: 2 → 4 → 8 TMSs followed by loss of a TMS either at the N- or C-terminus, depending on the family, to give the more frequent 7 TMS topology. PMID:22192777

  17. Effects of water soaking and/or sodium polystyrene sulfonate addition on potassium content of foods.

    PubMed

    Picq, Christian; Asplanato, Marion; Bernillon, Noémie; Fabre, Claudie; Roubeix, Mathilde; Ricort, Jean-Marc

    2014-09-01

    In this study, we determined, by atomic absorption spectrophotometry, the potassium amount leached by soaking or boiling foods identified by children suffering from chronic renal failure as "pleasure food" and that they cannot eat because of their low-potassium diet, and evaluated whether addition of sodium polystyrene sulfonate resin (i.e. Kayexalate®) during soaking or boiling modulated potassium loss. A significant amount of potassium content was removed by soaking (16% for chocolate and potato, 26% for apple, 37% for tomato and 41% for banana) or boiling in a large amount of water (73% for potato). Although Kayexalate® efficiently dose-dependently removed potassium from drinks (by 48% to 73%), resin addition during soaking or boiling did not eliminate more potassium from solid foods. Our results therefore provide useful information for dietitians who elaborate menus for people on potassium-restricted diets and would give an interesting alternative to the systematic elimination of all potassium-rich foods from their diet.

  18. Effect of linear alkylbenzene sulfonate (LAS) on human intestinal Caco-2 cells at non cytotoxic concentrations.

    PubMed

    Bradai, Mohamed; Han, Junkyu; Omri, Abdelfatteh El; Funamizu, Naoyuki; Sayadi, Sami; Isoda, Hiroko

    2016-08-01

    Linear alkylbenzene sulfonate (LAS) is a cytotoxic synthetic anionic surfactant widely present in the environment due to its large-scale production and intensive use in the detergency field. In this study, we investigated the effect of LAS (CAS No. 25155-30-0) at non cytotoxic concentrations on human intestinal Caco-2 cells using different in vitro bioassays. As results, LAS increased Caco-2 cell proliferation at concentrations ranging from 1 to 15 ppm, more significantly for shorter exposure time (24 h), confirmed using flow cytometry and trypan blue exclusion methods. Moreover, proteomics analysis revealed that this effect was associated with an over-expression of elongation factor 2 and dipeptidyl peptidase 3, and a down-regulation of 14-3-3 protein theta, confirmed at mRNA level using real-time PCR. These findings suggest that LAS at non cytotoxic concentrations, similar to those observed at wastewater treatment plants outlets, increases the growth rate of colon cancer cells, raising thereby its tumor promotion effect potential.

  19. A strategy to modulate the electrophoretic behavior in plastic microchips using sodium polystyrene sulfonate.

    PubMed

    Guo, Jinxiu; Chen, Yu; Zhao, Lizhi; Sun, Ping; Li, Hongli; Zhou, Lei; Wang, Xiayan; Pu, Qiaosheng

    2016-12-16

    Plastic microchips have been broadly used as disposable microfluidic devices, but the poorly defined surface properties limit their application. Herein, we proved that an anionic polymer could be used as the background electrolyte (BGE) to provide a strong and stable cathodic electroosmotic flow (EOF) and modulate the electrophoretic behavior for efficient separation in relative thicker microchannels (∼75μm id). A cathodic EOF of ∼3.3×10(-4)cm(2)V(-1)s(-1) was maintained using sodium polystyrene sulfonate (PSSNa) with a molecular weight of 5×10(5) as the BGE, which ensured fluorescein isothiocyanate labeled biogenic amines (BAs) appeared ahead of other components in the electropherograms obtained with microchips of cyclic olefin copolymer. Four selected BAs appeared within 50s and theoretical plate numbers of 8.0×10(5)/m were achieved. The role of PSSNa was evaluated with streaming potential, dynamic light scattering, contact angle and atomic force microscopy. Its functionalities as surface modifier, viscosity regulator and pseudostationary phase were also confirmed. The proposed electrophoretic method was applied in the fast determination of BAs in fish meat samples.

  20. Sulfonated aluminum phthalocyanines for two-photon photodynamic cancer therapy: the effect of the excitation wavelength

    NASA Astrophysics Data System (ADS)

    Wang, J.; Li, W.; Yu, H. B.; Cheung, N. H.; Chen, J. Y.

    2014-03-01

    Sulfonated aluminum phthalocyanine (AlPcS) is a well-studied photosensitizer which has been widely used in research and in clinical applications of the photodynamic therapy of cancers. Conventionally, one-photon excitation was used, but it was unknown whether two-photon excitation of AlPcS was equally effective. In this study, the two-photon absorption cross sections of AlPcS at near infrared wavelengths were deduced from femtosecond (fs) laser-induced fluorescence. We found that the two-photon absorption cross section of AlPcS was strongly dependent on the excitation wavelength. It was about 19 GM when excited at 800 nm, but grew to 855 GM when excited at 750 nm. The 750 nm fs-laser-induced fluorescence images of AlPcS in human nasopharyngeal carcinoma cells were clearly visible while the corresponding images were very dim when excited at 800 nm. Singlet oxygen production was 13 times higher when excited at 750 nm relative to 800 nm. Our subsequent in vitro experiments showed that 750 nm two-photon excitation with an unfocused fs laser beam damaged cancer cells in a light-dose-dependent manner typical of photodynamic therapy (PDT). The killing at 750 nm was about 9-10 times more efficient than at 800 nm. These results demonstrated for the first time that AlPcS has good potential for two-photon PDT of cancers.

  1. Highly efficient sulfonated polybenzimidazole as a proton exchange membrane for microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Singha, Shuvra; Jana, Tushar; Modestra, J. Annie; Naresh Kumar, A.; Mohan, S. Venkata

    2016-06-01

    Although microbial fuel cells (MFCs) represent a promising bio-energy technology with a dual advantage (i.e., electricity production and waste-water treatment), their low power densities and high installation costs are major impediments. To address these bottlenecks and replace highly expensive Nafion, which is a proton exchange membrane (PEM), the current study focuses for the first time on membranes made from an easily synthesizable and more economical oxy-polybenzimidazole (OPBI) and its sulfonated analogue (S-OPBI) as alternate PEMs in single-chambered MFCs. The S-OPBI membrane exhibits better properties, with high water uptake, ion exchange capacity (IEC) and proton conductivity and a comparatively smaller degree of swelling compared to Nafion. The membrane morphology is characterized by atomic force microscopy, and the bright and dark regions of the S-OPBI membrane reveals the formation of ionic domains in the matrix, forming continuous water nanochannels when doped with water. These water-filled nanochannels are responsible for faster proton conduction in S-OPBI than in Nafion; therefore, the power output in the MFC with S-OPBI as the PEM is higher than in other MFCs. The open circuit voltage (460 mV), current generation (2.27 mA) and power density profile (110 mW/m2) as a function of time, as well as the polarization curves, exhibits higher current and power density (87.8 mW/m2) with S-OPBI compared to Nafion as the PEM.

  2. Determination and occurrence of secondary alkane sulfonates (SAS) in aquatic environments.

    PubMed

    Baena-Nogueras, Rosa María; González-Mazo, Eduardo; Lara-Martín, Pablo A

    2013-05-01

    A new methodology has been developed for the determination of secondary alkane sulfonates (SAS), an anionic surfactant, in environmental matrices. Sediment and sludge samples were extracted using pressurized liquid extraction and sonication, whereas wastewater and surface water samples were processed using solid-phase extraction. Extraction recoveries were acceptable for both aqueous (78-120%) and solid samples (83-100%). Determination of SAS was carried out by high or ultra performance liquid chromatography - mass spectrometry using ion trap and time-of-flight detectors. The methodology was applied to samples from Guadalete River (SW Spain), where SAS concentrations below 1 μg L(-1) were measured in surface water, and from 72 to 9737 μg kg(-1) in sediments. Differential partitioning was observed for SAS homologues as those having a longer hydrocarbon chain which preferentially sorbed onto particulate matter. A preliminary environmental risk assessment also showed that SAS measured levels were not harmful to the aquatic community in the sampling area.

  3. Removal of textile dyes and metallic ions using polyelectrolytes and macroelectrolytes containing sulfonic acid groups.

    PubMed

    Caldera Villalobos, M; Peláez Cid, A A; Herrera González, Ana M

    2016-07-15

    This work reports the removal of textile dyes and metallic ions by means of adsorption and coagulation-flocculation using two polyelectrolytes and two macroelectrolytes containing sulfonic acid groups. The adsorption of textile dyes was studied in aqueous solutions containing cationic dyes and in wastewater containing a vat dye. Also, removal of vat and naphthol dyes was studied using the process of coagulation-flocculation. The results show these materials possess elevated adsorption capacity, and they accomplished removal rates above 97% in aqueous solutions. The removal of the vat dye improved the quality of the wastewater notably, and an uncolored effluent was obtained at the end of the treatment. The treatment using adsorption decreased the values for coloration, conductivity, suspended solids, and pH. The removal of vat and naphthol dyes by means of coagulation-flocculation was studied as well, and removal rates of 90% were obtained. The polyelectrolytes and macroelectrolytes also proved effective in the adsorption of metallic ions in wastewater. The treatment using adsorption accomplished high removal rates of metallic ions, and it showed greater selectivity towards Cu(2+), Fe(3+) and Pb(2+). A decrease in the content of solids as well as the values for COD and conductivity was observed in the wastewater as well. The analyses of FT-IR indicated that cationic dyes and metallic ions were chemisorbed by means of ionic exchange.

  4. Sulfonated silica-based fuel cell electrode structures for low humidity applications

    NASA Astrophysics Data System (ADS)

    Eastcott, Jennie I.; Easton, E. Bradley

    2014-01-01

    Ceramic carbon electrodes (CCEs) are prospective candidates for use in proton exchange membrane fuel cells due to their high surface area, water retention properties, and durable nature. We have determined that incorporating small amounts of sulfonated silane in the CCE structure can lead to a profound enhancement of catalytic activity and proton conductivity. To evaluate the usefulness of a new catalyst layer for practical use, performance of the materials under various conditions must be considered. We have compared the properties of membrane electrode assemblies (MEA) prepared with CCE cathode catalyst layers to that of an MEA prepared with Nafion-based cathode catalyst layers. The MEAs were characterized via transmission electron microscopy, thermogravimetric analysis, infrared spectroscopy, and BET analysis. Fuel cell performance using different cathode gas relative humidity (RH) feed conditions was monitored using electrochemical impedance spectroscopy and polarization curves. Our CCE cathode materials maintained stable performance and had improved water management capabilities at low relative humidities, whereas Nafion-containing cathodes have performed poorly. The enhanced performance and tolerance to low RH is explained in terms of water retention within the CCE-based MEA.

  5. Sulfonation of phenols extracted from the pyrolysis oil of oil palm shells for enhanced oil recovery.

    PubMed

    Awang, Mariyamni; Seng, Goh Meng

    2008-01-01

    The cost of chemicals prohibits many technically feasible enhanced oil recovery methods to be applied in oil fields. It is shown that by-products from oil palm processing can be a source of valuable chemicals. Analysis of the pyrolysis oil from oil palm shells, a by-product of the palm oil industry, reveals a complex mixture of mainly phenolic compounds, carboxylic acids, and aldehydes. The phenolic compounds were extracted from the pyrolysis oil by liquid-liquid extraction using alkali and an organic solvent and analyzed, indicating the presence of over 93% phenols and phenolic compounds. Simultaneous sulfonation and alkylation of the pyrolysis oil was carried out to produce surfactants for application in oil fields. The lowest measured surface tension and critical micelle concentration was 30.2 mNm(-1) and 0.22 wt%, respectively. Displacement tests showed that 7-14% of the original oil in place was recovered by using a combination of surfactants and xanthan (polymer) as additives.

  6. Toxicokinetics of seven perfluoroalkyl sulfonic and carboxylic acids in pigs fed a contaminated diet.

    PubMed

    Numata, Jorge; Kowalczyk, Janine; Adolphs, Julian; Ehlers, Susan; Schafft, Helmut; Fuerst, Peter; Müller-Graf, Christine; Lahrssen-Wiederholt, Monika; Greiner, Matthias

    2014-07-16

    The transfer of a mixture of perfluoroalkyl acids (PFAAs) from contaminated feed into the edible tissues of 24 fattening pigs was investigated. Four perfluoroalkyl sulfonic (PFSAs) and three perfluoroalkyl carboxylic acids (PFCAs) were quantifiable in feed, plasma, edible tissues, and urine. As percentages of unexcreted PFAA, the substances accumulated in plasma (up to 51%), fat, and muscle tissues (collectively, meat 40-49%), liver (under 7%), and kidney (under 2%) for most substances. An exception was perfluorooctanesulfonic acid (PFOS), with lower affinity for plasma (23%) and higher for liver (35%). A toxicokinetic model is developed to quantify the absorption, distribution, and excretion of PFAAs and to calculate elimination half-lives. Perfluorohexanoic acid (PFHxA), a PFCA, had the shortest half-life at 4.1 days. PFSAs are eliminated more slowly (e.g., half-life of 634 days for PFOS). PFAAs in pigs exhibit longer elimination half-lives than in most organisms reported in the literature, but still shorter than in humans.

  7. Discovery and Characterization of Diazenylaryl Sulfonic Acids as Inhibitors of Viral and Bacterial Neuraminidases.

    PubMed

    Hoffmann, Anja; Richter, Martina; von Grafenstein, Susanne; Walther, Elisabeth; Xu, Zhongli; Schumann, Lilia; Grienke, Ulrike; Mair, Christina E; Kramer, Christian; Rollinger, Judith M; Liedl, Klaus R; Schmidtke, Michaela; Kirchmair, Johannes

    2017-01-01

    Viral neuraminidases are an established drug target to combat influenza. Severe complications observed in influenza patients are primarily caused by secondary infections with e.g., Streptococcus pneumoniae. These bacteria engage in a lethal synergism with influenza A viruses (IAVs) and also express neuraminidases. Therefore, inhibitors with dual activity on viral and bacterial neuraminidases are expected to be advantageous for the treatment of influenza infections. Here we report on the discovery and characterization of diazenylaryl sulfonic acids as dual inhibitors of viral and Streptococcus pneumoniae neuraminidase. The initial hit came from a virtual screening campaign for inhibitors of viral neuraminidases. For the most active compound, 7-[2-[4-[2-[4-[2-(2-hydroxy-3,6-disulfo-1-naphthalenyl)diazenyl]-2-methylphenyl]diazenyl]-2-methylphenyl]diazenyl]-1,3-naphthalenedisulfonic acid (NSC65847; 1), the Ki-values measured in a fluorescence-based assay were lower than 1.5 μM for both viral and pneumococcal neuraminidases. The compound also inhibited N1 virus variants containing neuraminidase inhibitor resistance-conferring substitutions. Via enzyme kinetics and nonlinear regression modeling, 1 was suggested to impair the viral neuraminidases and pneumococcal neuraminidase with a mixed-type inhibition mode. Given its antiviral and antipneumococcal activity, 1 was identified as a starting point for the development of novel, dual-acting anti-infectives.

  8. Discovery and Characterization of Diazenylaryl Sulfonic Acids as Inhibitors of Viral and Bacterial Neuraminidases

    PubMed Central

    Hoffmann, Anja; Richter, Martina; von Grafenstein, Susanne; Walther, Elisabeth; Xu, Zhongli; Schumann, Lilia; Grienke, Ulrike; Mair, Christina E.; Kramer, Christian; Rollinger, Judith M.; Liedl, Klaus R.; Schmidtke, Michaela; Kirchmair, Johannes

    2017-01-01

    Viral neuraminidases are an established drug target to combat influenza. Severe complications observed in influenza patients are primarily caused by secondary infections with e.g., Streptococcus pneumoniae. These bacteria engage in a lethal synergism with influenza A viruses (IAVs) and also express neuraminidases. Therefore, inhibitors with dual activity on viral and bacterial neuraminidases are expected to be advantageous for the treatment of influenza infections. Here we report on the discovery and characterization of diazenylaryl sulfonic acids as dual inhibitors of viral and Streptococcus pneumoniae neuraminidase. The initial hit came from a virtual screening campaign for inhibitors of viral neuraminidases. For the most active compound, 7-[2-[4-[2-[4-[2-(2-hydroxy-3,6-disulfo-1-naphthalenyl)diazenyl]-2-methylphenyl]diazenyl]-2-methylphenyl]diazenyl]-1,3-naphthalenedisulfonic acid (NSC65847; 1), the Ki-values measured in a fluorescence-based assay were lower than 1.5 μM for both viral and pneumococcal neuraminidases. The compound also inhibited N1 virus variants containing neuraminidase inhibitor resistance-conferring substitutions. Via enzyme kinetics and nonlinear regression modeling, 1 was suggested to impair the viral neuraminidases and pneumococcal neuraminidase with a mixed-type inhibition mode. Given its antiviral and antipneumococcal activity, 1 was identified as a starting point for the development of novel, dual-acting anti-infectives. PMID:28261167

  9. Sulfonated graphene oxide and its nanocomposites with electroactive conjugated polymer as effective pseudocapacitor electrode materials.

    PubMed

    Ehsani, A; Kowsari, E; Boorboor Ajdari, F; Safari, R; Mohammad Shiri, H

    2017-07-01

    In this work, we synthesized amine functionalized graphene oxide (GOA), by using of 1-methyl, 3-butyl Imidazole ionic liquid, triphenylphosphine, 1,6-diamino hexane in DMSO medium. Afterward, dried GOA used for sulfonated graphene oxide (GOS). For improving electrochemical properties of the poly ortho aminophenol (POAP), we fabricated POAP/GOS films by electro-polymerization of POAP in the presence of GOS to serve as the active electrode for electrochemical supercapacitor. Different electrochemical methods including galvanostatic charge-discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy are carried out in order to investigate the performance of the system. Finally, the local charge and energy transfer of the molecular system is calculated, using DFT/AIM theories. Results show that the oxygen and nitrogen atoms of phenyl (Ph)/(Ph-OH) rings and -Ph-CO-N-R-N-R″ -SO3H ended functional group, play domain role in intra-molecular charge and energy transfer. The major aim of this computational study method is to propose or effective design electro-chemical molecular systems having different atomic basins/functional groups response (sensitivities) to external voltage. This work introduces new most efficient materials for electrochemical redox capacitors with advantages including ease synthesis, high active surface area and stability in an aqueous electrolyte.

  10. Preparation of Chitosan/Polystyrene Sulfonate Multilayered Composite Metal Nanoparticles and Its Application.

    PubMed

    Xiong, Fangxin; Chen, Chunxiao; Liu, Shantang

    2016-06-01

    Metal-Chitosan (CTS) composite was first synthesized through the metal composition of chitosan (CTS) and metal ions. The formed composite was alternately deposited on the base with sodium polystyrene sulfonate (PSS) through a layer-by-layer self-assembling technique, followed by an in situ reduction by sodium borohydride to produce a polyelectrolyte nanocomposite thin film containing metal nanoparticles. Assembly, surface morphology and electrochemical properties of the composite membrane were analyzed by UV-visible absorption spectroscopy (UV-vis), atomic force microscopy (AFM) and cyclic voltammetry (CV). The UV-Vis results indicated that the absorbance of the multilayer film at the characteristic absorption peak increased as the membrane bilayers increased, in a good linear relationship, which demonstrated that the multilayer film was uniformly assembled on the base. AFM images showed that the surface of the multilayer thin-film composite had some degree of roughness and metal nanoparticles of 10-20 nm in size were generated on the membrane. The CV results indicated that the metal nanocomposite film had excellent electrocatalytic activity to glucose and had a potential for applications in electrochemical sensors.

  11. Adsorption of perfluorooctane sulfonate on soils: Effects of soil characteristics and phosphate competition.

    PubMed

    Qian, Jin; Shen, Mengmeng; Wang, Peifang; Wang, Chao; Hou, Jun; Ao, Yanhui; Liu, Jingjing; Li, Kun

    2017-02-01

    Perfluorooctane sulfonate (PFOS) is an emerging contaminant, whose presence has been detected in different compartments of the environment in many countries. In this study, the effects of soil characteristics and phosphate competition on the adsorption of PFOS on soils were investigated. Results from batch sorption experiments showed that all the adsorption isotherms of PFOS on three tested soils were nonlinear. In experiments without the addition of phosphate (P) to the soil solution, the Freundlich sorption affinity (Kf) of PFOS on S (original soil), S1 (soil from which soil organic matter (SOM) had been removed), and S2 (soil from which both SOM and ferric oxides had been removed) were 23.13, 10.37 and 15.95, respectively. The results suggested that a high amount of SOM in soil can increase the sorption affinity of PFOS on soils and that a greater amount of ferric oxides can reduce it. The addition of P in the soil solution reduced the Kf of PFOS on S, S1, and S2 by approximately 25%, 50%, and 15%, respectively. For the binary system of PFOS and P, soil with higher ferric oxide content showed greater Kf reduction after P addition; whereas soil with higher SOM content showed less Kf reduction. Our results suggest that for soils dominated by ferric oxides, P is a more effective competitor than PFOS for the adsorption sites in the binary system; whereas in soils containing more SOM, P is a weak competitor.

  12. Assessment of Perfluorooctane Sulfonate and Perfluorooctanoic Acid Exposure Through Fish Consumption in Italy

    PubMed Central

    Barbarossa, Andrea; Gazzotti, Teresa; Farabegoli, Federica; Mancini, Francesca R.; Zironi, Elisa; Busani, Luca; Pagliuca, Giampiero

    2016-01-01

    Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are pollutants of anthropic origin with possible side effects on human health. Diet, and in particular fish and seafood, is considered the major intake pathway for humans. The present study investigated the levels of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) contamination in twenty-five samples of fresh fillet of five widely consumed fish species purchased from large retailers in Italy, to be used for an estimation of the Italian population exposure to these contaminants. PFOS and PFOA were found in all samples, at concentrations up to 1896 (mean=627 ng/kg) and 487 ng/kg (mean = 75 ng/kg), respectively, confirming the role of fish as high contributor to human exposure. However, a remarkable inter-species variability was observed, and multiple factors were suggested as potentially responsible for such differences, suggesting that the preferential consumption of certain species could likely increase the intake, and thus the exposure. The exposure estimates for both average and high fish consumers resulted far below the tolerable daily intakes for PFOS and PFOA in all age groups, confirming the outcomes of EFSA’s scientific report. In particular, the calculated total dietary exposure for the 95th percentile consumers belonging to the toddler age class, the most exposed group, resulted equal to 9.72 ng/kg body weight (BW)/day for PFOS and 8.39 ng/kg BW/day for PFOA. PMID:28058243

  13. Esterification free fatty acid in palm fatty acid distillate using sulfonated rice husk ash catalyst

    NASA Astrophysics Data System (ADS)

    Hidayat, Arif; Sutrisno, Bachrun

    2017-01-01

    Indonesia, as one of the biggest palm oil producers and exporters in the world, is producing large amounts of low-grade oil such as Palm Fatty Acid Distillate (PFAD) from palm oil industries. The use of PFAD can reduce the cost of biodiesel production significantly, which makes PFAD a highly potential alternative feedstock for biodiesel production. In this paper, the esterification of free fatty acid (FFA) on PFAD was studied using rice husk ash (RHA) as heterogeneous catalyst. The rice husk ash catalyst was synthesized by sulfonation using concentrated sulfuric acid. The RHA catalyst were characterized by using different techniques, such as porosity analysis, Fourier transform infrared (FT-IR) spectroscopy, total number of acid sites and elemental analysis. The effects of the molar ratio of methanol to PFAD (1-10%), the molar ratio of methanol to PFAD (4:1-10:1), and the reaction temperature (40-60°C) were studied for the conversion of FFA to optimize the reaction conditions. The results showed that the optimal conditions were an methanol to PFAD molar ratio of 10:1, the catalyst amount of 10 wt% of PFAD, and reaction temperature of 60°C.

  14. Morphology Effect on Proton Dynamics in Nafion® 117 and Sulfonated Polyether Ether Ketone

    NASA Astrophysics Data System (ADS)

    Leong, Jun Xing; Diño, Wilson Agerico; Ahmad, Azizan; Daud, Wan Ramli Wan; Kasai, Hideaki

    2016-09-01

    We report results of our experimental and theoretical studies on the dynamics of proton conductivity in Nafion® 117 and self-fabricated sulfonated polyether ether ketone (SPEEK) membranes. Knowing that the presence of water molecules in the diffusion process results in a lower energy barrier, we determined the diffusion barriers and corresponding tunneling probabilities of Nafion® 117 and SPEEK system using a simple theoretical model that excludes the medium (water molecules) in the initial calculations. We then propose an equation that relates the membrane conductivity to the tunneling probability. We recover the effect of the medium by introducing a correction term into the proposed equation, which takes into account the effect of the proton diffusion distance and the hydration level. We have also experimentally verified that the proposed equation correctly explain the difference in conductivity between Nafion® 117 and SPEEK. We found that membranes that are to be operated in low hydration environments (high temperatures) need to be designed with short diffusion distances to enhance and maintain high conductivity.

  15. Electrochemical investigation of methyl parathion at gold-sodium dodecylbenzene sulfonate nanoparticles modified glassy carbon electrode.

    PubMed

    Li, Chunya; Wang, Zhengguo; Zhan, Guoqin

    2011-01-01

    A gold/sodium dodecylbenzene sulfonate nanoparticles modified glassy carbon electrode (nano-Au/SDBS/GCE) was electrochemically fabricated with a constant potential at -0.4V. The obtained nano-Au/SDBS/GCE was characterized with scanning electronic microscopy, X-ray photoelectron spectroscopy and electrochemical techniques. Electrochemical behaviors of methyl parathion at the nano-Au/SDBS/GCE were thoroughly investigated. Compared to the unmodified electrode, the peak current obviously increased and the oxidation peak potential negatively shifted. These changes indicated that the composite nanoparticles possess good electrocatalytic performance on the electrochemical reaction of methyl parathion. Experimental parameters such as deposition time, pH value and accumulation conditions were optimized. Under optimum conditions, the peak current corresponding to the oxidation of the hydroxylamine group was found in a good linear relationship with the methyl parathion concentration. In addition, a calibration curve with excellent linearity was obtained in the concentration range from 5.0×10(-7)molL(-1) to 1.0×10(-4)molL(-1) with an estimated detection limit of 8.6×10(-8)molL(-1) (S/N=3). The successful determination of methyl parathion in real samples demonstrated the usefulness and potential applications of this method.

  16. The Liebermann-Burchard reaction: sulfonation, desaturation, and rearrangment of cholesterol in acid.

    PubMed

    Xiong, Quanbo; Wilson, William K; Pang, Jihai

    2007-02-01

    In the Liebermann-Burchard (LB) colorimetric assay, treatment of cholesterol with sulfuric acid, acetic anhydride, and acetic acid elicits a blue color. We studied the reactivity of cholesterol under LB conditions and provide definitive NMR characterization for approximately 20 products, whose structure and distribution suggest the following mechanistic picture. The major reaction pathways do not involve cholestadienes, i-steroids, or cholesterol dimers, as proposed previously. Instead, cholesterol and its acetate and sulfate derivatives undergo sulfonation at a variety of positions, often with skeletal rearrangements. Elimination of an SO(3)H group as H(2)SO(3) generates a new double bond. Repetition of this desaturation process leads to polyenes and ultimately to aromatic steroids. Linearly conjugated polyene cations can appear blue but form too slowly to account for the LB color response, whose chemical origin remains unidentified. Nevertheless, the classical polyene cation model is not excluded for Salkowski conditions (sulfuric acid), which immediately generate considerable amounts of cholesta-3,5-diene. Some rearrangements of cholesterol in H(2)SO(4) resemble the diagenesis pathways of sterols and may furnish useful lipid biomarkers for characterizing geological systems.

  17. The Type B Flagellin of Hypervirulent Clostridium difficile Is Modified with Novel Sulfonated Peptidylamido-glycans*

    PubMed Central

    Bouché, Laura; Panico, Maria; Hitchen, Paul; Binet, Daniel; Sastre, Federico; Faulds-Pain, Alexandra; Valiente, Esmeralda; Vinogradov, Evgeny; Aubry, Annie; Fulton, Kelly; Twine, Susan; Logan, Susan M.; Wren, Brendan W.; Morris, Howard R.

    2016-01-01

    Glycosylation of flagellins is a well recognized property of many bacterial species. In this study, we describe the structural characterization of novel flagellar glycans from a number of hypervirulent strains of C. difficile. We used mass spectrometry (nano-LC-MS and MS/MS analysis) to identify a number of putative glycopeptides that carried a variety of glycoform substitutions, each of which was linked through an initial N-acetylhexosamine residue to Ser or Thr. Detailed analysis of a LLDGSSTEIR glycopeptide released by tryptic digestion, which carried two variant structures, revealed that the glycopeptide contained, in addition to carbohydrate moieties, a novel structural entity. A variety of electrospray-MS strategies using Q-TOF technology were used to define this entity, including positive and negative ion collisionally activated decomposition MS/MS, which produced unique fragmentation patterns, and high resolution accurate mass measurement to allow derivation of atomic compositions, leading to the suggestion of a taurine-containing peptidylamido-glycan structure. Finally, NMR analysis of flagellin glycopeptides provided complementary information. The glycan portion of the modification was assigned as α-Fuc3N-(1→3)-α-Rha-(1→2)-α-Rha3OMe-(1→3)-β-GlcNAc-(1→)Ser, and the novel capping moiety was shown to be comprised of taurine, alanine, and glycine. This is the first report of a novel O-linked sulfonated peptidylamido-glycan moiety decorating a flagellin protein. PMID:27758867

  18. Toxicological evaluation of peroxy sulfonated oleic acid (PSOA) in subacute and developmental toxicity studies.

    PubMed

    Pechacek, Nathan; Laidlaw, Karen; Clubb, Stephanie; Aulmann, Walter; Osorio, Magdalena; Caudill, Jeff

    2013-12-01

    Peroxy sulfonated oleic acid (PSOA) is a new coupler used in sanitizing solutions primarily for the food and beverage industry. The toxicity of PSOA was evaluated in a 28-day repeat dose study according to OECD 407 guidelines with a 14-day recovery period and a developmental toxicity study according to OECD 414 guidelines. In both studies, PSOA was administered once daily via gavage at 0, 5, 15 and 50 mg/kg/day to Sprague-Dawley rats. Due to its corrosive properties, the highest test concentration was restricted to 0.5%. No findings related to PSOA administration were observed for the 28-day repeat-dose study and the NOEL is 50 mg/kg/day. Additionally, no impairment of the mucous membranes of the gastrointestinal tract was observed up to 0.5%, which is considered the NOEC in terms of local toxicity. For the developmental study, an embryo-fetal NOEL of 50 mg/kg/day was identified and the maternal NOEL is considered to be 15 mg/kg/day, based on slight reductions in maternal body weight and food consumption, as well as a modest increase in the incidence of clinical observations at the high dose. These findings demonstrate that PSOA appears to have minimal potential to induce toxicity associated with repeat-dose or developmental exposures.

  19. Influence of volatile fatty acid concentration stability on anaerobic degradation of linear alkylbenzene sulfonate.

    PubMed

    Okada, Dagoberto Y; Delforno, Tiago P; Esteves, Andressa S; Polizel, Juliana; Hirasawa, Julia S; Duarte, Iolanda C S; Varesche, Maria B A

    2013-10-15

    Linear alkylbenzene sulfonate (LAS) is an anionic surfactant used in cleaning products, which is usually found in wastewaters. Despite the greater LAS removal rate related to a lower concentrations of volatile fatty acids (VFA), the influence of different ranges of VFA on LAS degradation is not known. LAS degradation was evaluated in upflow anaerobic sludge blanket (UASB) and expanded granular sludge bed (EGSB) reactors at different ranges of VFA concentrations. The reactors were fed with a synthetic wastewater containing LAS (14 mg/L). A greater LAS removal rate (40-80%) was related to the lower and narrower range of acetic acid concentration (1-22 mg/L) in the EGSB reactor. In the UASB reactor, the acetic acid concentrations presented a wider range (2-45 mg/L), and some low LAS removal rates (around 20-25%) were observed even at low acetic acid concentrations (<10 mg/L). The high recirculation rate in the EGSB reactor improved substrate-biomass contact, which resulted in a narrower range of VFA and greater LAS removal rate.

  20. Predicting the Solution Morphology of a Sulfonated Block Copolymer in Binary Solvent Mixtures

    NASA Astrophysics Data System (ADS)

    Griffin, Philip; Salmon, Grace; Ford, Jamie; Winey, Karen

    2015-03-01

    The physicochemical properties of solvent-casted block copolymer films are highly dependent on the microscopic morphology of the solutions from which they are cast. In order to achieve macroscopically homogenous polymer solutions, binary or higher-degree solvent mixtures are often required, which introduces additional complexity in understanding the molecular level interactions that control block copolymer self-assembly in solution. Using small angle x-ray scattering, we have explored the solution morphology in ternary blends of a sulfonated pentablock copolymer in select binary solvent mixtures over a range of solvent compositions and polymer concentrations. We have found that the solution morphologies in these ternary blends depend strongly on the composition of the solvent mixture. Furthermore, we demonstrate that the solvent-composition-dependent morphologies can be accurately predicted by quantifying the polymer/solvent interactions using Hansen solubility parameters. These studies are an important step toward developing a complete and predictive understanding of the solution morphology of complex polymer/solvent mixtures.

  1. Evaluation of a laboratory-generated NOEC for linear alkylbenzene sulfonate in outdoor experimental streams

    SciTech Connect

    Fairchild, J.F.; Dwyer, F.J.; Point, T.W. la; Burch, S.A.; Ingersoll, C.G. . National Fisheries Contaminant Research Center)

    1993-10-01

    Laboratory and field studies were conducted with linear alkylbenzene sulfonate (LAS) to evaluate the use of the laboratory-generated NOECs for protecting aquatic organisms in outdoor experimental streams. Fathead minnows (Pimephales promelas) and freshwater amphipods (Hyalella azteca) were exposed in the laboratory to an environmentally realistic mixture of LAS for 7 d; fathead minnows were also exposed in a 28-d study. Calculated NOEC values based on survival and growth ranged from 0.3 to 0.9 mg/L for fathead minnows and from 0.6 to 1.4 mg/L for amphipods. Toxicity of LAS in 4-, 7-, and 28-d exposured of fathead minnows was similar because mortality occurred within the initial 24 h of exposure; mortality was more sensitive than growth as a chronic end point. The addition of 5% sewage effluent to well and stream water had little effect on the bioavailability of LAS; however, total organic carbon levels were low in all treatments. A 45-d exposure of three outdoor experimental streams to 0.36 mg/L LAS had no effects on survival of fathead minnows or amphipods, dynamics of benthic invertebrates, growth of periphyton, or processing of detrital leaves. Results indicated that the laboratory-generated NOEC for LAS was protective of experimental stream communities under the studied conditions.

  2. [Calcium polystyrene sulfonate induced colonic necrosis in patient with chronic kidney disease].

    PubMed

    Lee, Sung Hoa; Kim, Sung Jung; Kim, Go Eun; Lee, Woo Jin; Hong, Won Ki; Baik, Gwang Ho; Choi, Young Hee; Kim, Dong Joon

    2010-04-01

    A 63-year-old woman was admitted due to right upper quadrant abdominal pain. She was going through hemodialysis due to end stage renal disease and taking calcium polystyrene sulfonate orally and rectally due to hyperkalemia. Colonoscopy showed a circular ulcerative mass on the proximal ascending colon. Biopsy specimen from the mass showed inflammation and necrotic debris. It also revealed basophilic angulated crystals which were adherent to the ulcer bed and normal mucosa. These crystals were morphologically consistent with calcium polystyrene sulfonate. She was diagnosed with calcium polystyrene phosphate induced colonic necrosis and improved with conservative treatment.

  3. Activated-Sludge Nitrification in the Presence of Linear and Branched-Chain Alkyl Benzene Sulfonates

    PubMed Central

    Baillod, Charles R.; Boyle, W. C.

    1968-01-01

    The effects of biodegradable linear alkyl benzene sulfonate and branched-chain alkyl benzene sulfonate detergents on activated-sludge nitrification were investigated by administering a synthetic waste containing up to 23 mg of each detergent per liter to eight bench-scale, batch, activated-sludge units. It was found that both detergents tended to promote complete oxidation of ammonia to nitrate, whereas control units produced approximately equal amounts of nitrite and nitrate. Various hypotheses are offered to explain the phenomenon. PMID:5636474

  4. [Investigation on formation mechanism of secologanic acid sulfonates in sulfur-fumigated buds of Lonicera japonica].

    PubMed

    Guo, Ai-Li; Gao, Hui-Min; Chen, Liang-Mian; Zhang, Qi-Wei; Wang, Zhi-Min

    2014-05-01

    To investigate formation mechanism of secologanic acid sulfonates in sulfur-fumigated buds of Lonicera japonica, secologanic acid was enriched and purified from the sun-dried buds of L. japonica by various column chromatography on macroporus resin HPD-100, silica gel and ODS. The stimulation experiments of sulfur-fumigation process were carried out using secologanic acid reacted with SO2 in the aqueous solution. The reaction mechanism could be involved in the esterification or addition reaction. The present investigation provides substantial evidences for interpreting formation pathway of secologanic acid sulfonates in sulfur-fumigated buds of L. japonica.

  5. Monitoring the Tanford transition in beta-lactoglobulin by 8-anilino-1-naphthalene sulfonate and mass spectrometry.

    PubMed

    Santambrogio, Carlo; Grandori, Rita

    2008-12-01

    The fluorescent dye 8-anilino-1-naphthalene sulfonate (ANS) is known to interact with proteins by conformation-specific hydrophobic interactions and rather nonspecific electrostatic interactions. To which category the complexes detectable by mass spectrometry (MS) belong is still the subject of debate. Here, the Tanford transition in beta-lactoglobulin (BLG) is exploited as an experimental device to expose hydrophobic binding sites by an increase in pH, rather than, as usually done, by lowering the pH. Complex formation is monitored by electrospray ionization (ESI)-MS and fluorescence spectroscopy. Both techniques reveal stronger ANS binding to BLG at pH 7.9 than at pH 5.9, suggesting that dye binding inside the calyx, which is known to be hydrophobically driven in solution, can contribute to the complexes detected by ESI-MS. Electrostatic interactions between the protein and the ANS sulfonate group can only be weaker at pH 7.9 than at pH 5.9, supporting the interpretation of the results by the protein conformational change. Lysozyme is used as a negative control, which shows no variation in the interaction with ANS in the same range of pH, in the absence of conformational changes. However, comparison of MS and fluorescence data at variable pH for BLG and myoglobin (Mb) suggests that conformation-specific ANS binding to proteins is detectable by ESI-MS only inside well-structured cavities of folded structures, like the BLG calyx and apoMb heme pocket. Indeed, ANS interactions with highly dynamic structures or molten globules, although detectable in solution, are easily lost in the gas phase.

  6. Polymer Brushes Containing Sulfonated Sugar Repeat Units: Synthesis, Characterization and In Vitro Testing of Blood Coagulation Activation

    PubMed Central

    Ayres, N.; Holt, D. J.; Jones, C.F.; Corum, L. E.; Grainger, D. W.

    2009-01-01

    A new polymer brush chemistry containing sulfonated carbohydrate repeat units has been synthesized from silicon substrates using ATRP methods and characterized both in bulk and using surface analysis. The polymer brush was designed to act as a mimic for the naturally occurring sulfonated glycosaminoglycan, heparin, commonly used for modifying blood-contacting surfaces both in vitro and in vivo. Surface analysis showed conversion of brush saccharide precursor chemistry to the desired sulfonated polymer product. The sulfonated polymer brush surface was further analyzed using three conventional in vitro tests for blood compatibility -- plasma recalcification times, complement activation, and thrombin generation. The sulfonated polymer brush films on silicon oxide wafers exhibited better assay performance in these blood component assays than the unsulfonated sugar functionalized polymer brush in all tests performed. PMID:19859552

  7. Distribution of fluorescence decay times for 1-anilinonaphthalene-8-sulfonate in human oxyhemoglobin A1b solution

    NASA Astrophysics Data System (ADS)

    Drazdou, A. S.; Sobchuk, A. N.; Syakhovich, V. E.; Bokut, O. S.; Kvasyuk, E. I.; Bushuk, B. A.; Bokut, S. B.

    2012-07-01

    We have studied complex formation between molecules of the fluorescent probe 1-anilinonaphthalene-8-sulfonate (1,8-ANS) and the major form (A1) and a minor form (Ab) of hemoglobin. The contribution of the longlived component f3 to the kinetic curves for fluorescence decay in HbA1b solutions is 0.021-0.036, which indicates a dramatic decrease (compared with HbA1) in the accessibility of the central cavity of HbA1b for binding 1,8-ANS. Disappearance of the long-lived component f3 in the fluorescence decay kinetics of 1,8-ANS in HbA1b solutions in the presence of inositol hexaphosphate (IHP) suggests that the regulatory region of HbA1b is completely inaccessible for interaction both with the negatively charged molecules of the probe and with natural regulators of the transport function for this form of the heme protein.

  8. 2,3-Dicyano-4-[(4-methyl­phenyl­sulfon­yl)­oxy]phenyl 4-methyl­benzene­sulfonate

    PubMed Central

    Deng, Yanhua; Ma, Changqin; Zhang, Xiaomei

    2011-01-01

    In the title compound, C22H16N2O6S2, the dihedral angle formed by the mean planes of the two benzene rings of the 4-methyl­phenyl­sulfonate groups is 21.9 (1)° and these rings form dihedral angles of 48.26 (9) and 52.73 (9)° with the central benzene ring. PMID:21754170

  9. A new oxovanadium(IV) complex containing an O,N-bidentate Schiff base ligand: Synthesis at ambient temperature, characterization, crystal structure and catalytic performance in selective oxidation of sulfides to sulfones using H2O2 under solvent-free conditions

    NASA Astrophysics Data System (ADS)

    Menati, Saeid; Rudbari, Hadi Amiri; Khorshidifard, Mahsa; Jalilian, Fariba

    2016-01-01

    A new bidentate ON Schiff base ligand, HL, was synthesized by simple condensation reaction of isopropylamine and salicylaldehyde. Then by reaction of HL and VO(acac)2 in the ratio of 2:1 at ambient temperature, a new oxovanadium(IV) Schiff base complex, VOL2, was synthesized. The Schiff base ligand and its oxovanadium(IV) complex were characterized by elemental analyses, FT-IR, 1H NMR, 13C NMR and UV-visible spectroscopies. The crystal structure of oxovanadium(IV) complex, VOL2, was also determined by single crystal X-ray analysis. The vanadium center in this structure is coordinated to two bidentate Schiff base ligands with the two nitrogen and two phenolate oxygen atoms in equatorial positions and one oxo oxygen in the axial position to complete the distorted trigonal bipyramidal N2O3 coordination sphere. Catalytic performance of the VOL2 complex was studied in the selective oxidation of thioanisole with the green oxidant 35% aqueous H2O2 under solvent-free conditions and under organic solvents (EtOH, CHCl3, CH2Cl2, DMF, CH3CN, EtOAc) as a model. Due to better catalytic performance of the VOL2 complex under solvent-free conditions, this complex used for the oxidation of the different sulfides to the corresponding sulfones under solvent-free conditions. The use of hydrogen peroxide as oxidant and the absence of solvent makes these reactions interesting from environmental and economic points of view.

  10. Multi-block sulfonated poly(phenylene) copolymer proton exchange membranes

    DOEpatents

    Fujimoto, Cy H [Albuquerque, NM; Hibbs, Michael [Albuquerque, NM; Ambrosini, Andrea [Albuquerque, NM

    2012-02-07

    Improved multi-block sulfonated poly(phenylene) copolymer compositions, methods of making the same, and their use as proton exchange membranes (PEM) in hydrogen fuel cells, direct methanol fuel cells, in electrode casting solutions and electrodes. The multi-block architecture has defined, controllable hydrophobic and hydrophilic segments. These improved membranes have better ion transport (proton conductivity) and water swelling properties.

  11. FT-IR SOLUTION SPECTRA OF PROPYL SULFIDE, PROPYL SULFOXIDE, AND PROPYL SULFONE

    EPA Science Inventory

    FT-IR spectra were obtained of 0.5% volumetric solutions of propyl sulfide, propyl sulfoxide, and propyl sulfone in hexane, CCl4, CS2, and CHCl3 to assist in the assignment of FT-IR-PAS spectra of propyl sulfoxide sorbed within the structure of several peats and onto cellulose. T...

  12. EFFECTS OF PERFLUOROOCTANE SULFONATE (PFOS) ON THYROID HORMONE STATUS IN ADULT AND NEONATAL RATS

    EPA Science Inventory

    EFFECTS OF PERFLUOROOCTANE SULFONATE (PFOS) ON THYROID HORMONE STATUS IN ADULT AND NEONATAL RATS. M.N. Logan1, J.R. Thibodeaux2, R.G. Hanson2, C. Lau2. 1North Carolina Central University, Durham, NC, 2Reprod. Tox. Div. NHEERL, US EPA, Research Triangle Park, NC.

    Perfluor...

  13. Two new sesquiterpene lactones with the sulfonic acid group from Saussurea lappa.

    PubMed

    Yin, Hong-quan; Fu, Hong-wei; Hua, Hui-ming; Qi, Xiu-lan; Li, Wen; Sha, Yi; Pei, Yue-hu

    2005-07-01

    Two new sesquiterpene lactones with the unusual sulfonic acid group, 13-sulfo-dihydrosantamarine (1) and 13-sulfo-dihydroreynosin (2), have been isolated from the roots of Saussurea lappa C. Their structures, including the absolute configurations, were elucidated by spectroscopic methods.

  14. Jacobsen protocols for large-scale epoxidation of cyclic dienyl sulfones: application to the (+)-pretazettine core.

    PubMed

    Ebrahimian, G Reza; du Jourdin, Xavier Mollat; Fuchs, Philip L

    2012-05-18

    A Jacobsen epoxidation protocol using H2O2 as oxidant was designed for the large-scale preparation of various epoxy vinyl sulfones. A number of cocatalysts were screened, and pH control led to increased reaction rate, higher turnover number, and improved reliability.

  15. DETERMINATION OF ALKYLATED & SULFONATED DIPHENYL OXIDE SULFACTANT BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

    EPA Science Inventory

    Methods for the determination of the anionic surfactant Dowfax 8390 are described. Dowfax is a complex mixture of various alkylated and sulfonated diphenyl oxides. The primary component of Dowfax is monoalkylated disulfonated diphenyl oxide (MADS). This work uses ion pairing chro...

  16. To Bind or to Let Loose: Effectiveness of Sodium Polystyrene Sulfonate in Decreasing Serum Potassium

    PubMed Central

    Sandal, Shaifali; Karachiwala, Hatim; Noviasky, John; Wang, Dongliang; Elliott, William C.; Lehmann, David F.

    2012-01-01

    Background. The use of sodium polystyrene sulfonate in decreasing serum potassium has recently been questioned due to the lack of documented effectiveness. Methods. A retrospective cohort analysis of all hospitalized patients who received sodium polystyrene sulfonate over four months was performed. The change in serum potassium was noted over a period of 24 hours. Patients who received any other form of potassium-altering drug or treatment were excluded. Results. The administration of sodium polystyrene sulfonate reduced serum potassium by 16.7% (P < 0.001) as compared to the baseline serum potassium over a period of 24 hours. During this same time, no change in serum creatinine was identified (P = 0.73). In addition, there was no correlation between potassium and creatinine change (r2 = 0.0004 and P = 0.99). Patients with higher initial serum potassium (≥5.6 mEq/L) reduced their potassium concentration 4% more than those with initial serum potassium of <5.6 mEq/L; however, this reduction did not reach statistical significance (P = 0.32). There was no significant difference in the effectiveness of 15 gm and 30 gm resin preparation (P = 0.54). Thirteen deaths were noted in our cohort, of which one death was due to ischemic colitis. Conclusion. We conclude that sodium polystyrene sulfonate is effective in lowering serum potassium. PMID:23476770

  17. MATERNAL AND DEVELOPMENTAL TOXICITY OF PERFLUOROOCTANE SULFONATE (PFOS) IN THE MOUSE

    EPA Science Inventory

    MATERNAL AND DEVELOPMENTAL TOXICITY OF PERFLUOROOCTANE SULFONATE (PFOS) IN THE MOUSE. J.R. Thibodeaux1, R.G. Hanson1, B.E. Grey1, B.D. Barbee1, J.H. Richards2, J.L. Butenhoff3, J.M. Rogers1, C. Lau1. 1Reprod. Tox. Div., 2Exp. Tox. Div., NHEERL, ORD, US EPA, Research Triangle Pa...

  18. Distribution and excretion of perfluorooctane sulfonate (PFOS) in beef cattle (Bos taurus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perfluorooctane sulfonate (PFOS), a perfluoroalkyl surfactant used in many industrial products, is present in industrial wastes and in wastewater treatment plant biosolids. Biosolids are commonly applied to pastures and crops used for animal feed; consequently, PFOS may accumulate in the edible tis...

  19. Pneumocystis carinii mutations associated with sulfa and sulfone prophylaxis failures in immunocompromised patients.

    PubMed

    Armstrong, W; Meshnick, S; Kazanjian, P

    2000-01-01

    Recent studies have shown that mutations in two amino acid positions of the Pneumocystis carinii dihydropteroate synthase gene are significantly more common in immunocompromised patients with P. carinii pneumonia who fail sulfa or sulfone prophylaxis. This paper reviews the studies that suggest that these mutations may be responsible for some failures of prophylaxis in P. carinii.

  20. Effect of some petroleum sulfonate surfactants on the apparent water solubility of organic compounds

    SciTech Connect

    Kile, D.E.; Chiou, C.T. ); Helburn, R.S. )

    1990-02-01

    Water solubility enhancements of 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT) and 1,2,3-trichlorobenzene (TCB) by some commercial petroleum sulfonates (Petronate L, Petronate HL, and Pyronate 40) were studied at room temperature. Unlike conventional surfactants, the petroleum sulfonate surfactants are mixtures of sulfonated hydrocarbons and free mineral oils, which form stable emulsions in water and thus behave much like a bulk organic phase in concentrating organic solutes. The extent of solubility enhancement is linearly proportional to the concentration of the petroleum sulfonate-oil (PSO) emulsion, in contrast with the effect of a conventional surfactant in which a sharp inflection occurs in the vicinity of the critical micelle concentration (CMC). The enhancement effect of the PSO surfactant is 1.5-3 orders of magnitude greater than that of ordinary surfactant monomers below the CMC. The partition coefficient of the solute between the emulsified PSO phase and water (K{sub em}) is closely related to the nonpolar content of the PSO surfactant; the normalized K{sub em} values are about the same order of magnitude as the solvent (octanol)-water partition coefficients of the solutes.